Click here to watch the 'How to use RMPrepUSB' YouTube videos.
RMPrepUSB is a Windows utility that can be used to format any USB
storage device, e.g. USB Flash drive (UFD) or USB hard disk, as a bootable
device (but cannot be used on USB Floppy drives to format floppy disks). It can
be used to partition, format, write a Master Boot Record, partition table and/or
Volume Boot Record (sometimes called a Partition Boot Record) and operating
system boot code to a USB storage device (e.g. USB flash memory drive or USB
hard disk). It can also be used to
work on non-USB drives.
If you installed RMPrepUSB using the Installer, you can
easily uninstall it using the ‘uninstall RMPrepUSB’ entry in the Start Menu.
However, you do not need to install
RMPrepUSB (it is portable and will even run under BartPE or WinPE v1/v2/v3), just ensure that all the files are copied to a folder on your hard drive or storage drive.
Note: if running Win
PE you may need to copy the MSVBSM60.DLL from the WINPE_EXTRA folder to the
same folder that RMPrepUSB.exe is in. Also, if you are running under Win PE
v1/BartPE you may need to copy showdrive.exe file from the WINPE_EXTRA folder
(do not copy this file if running Windows XP+ though as it can cause
problems!) - showdrive auto-mounts a new drive after it has been formatted if the OS itself does not.
To start - select the Languagethat you want to use in the top-right hand box. RMPrepUSB will list all *.INI
files found in the .\LANG folder. Note that the translated files may be
slightly out of date, but if you select English
you will always get the latest version of help text. If you are running Windows XP, you may
need to install Asian language support (see FAQ Q32)
Please read the all the FAQs at the end of this document!
RMPrepUSB and RMPartUSB are
free (Freeware) for private use only; however
they are not Open Source programs. For commercial use and licensing please contact
[email protected]. Distribution, sale, or use in
a commercial solution is forbidden without permission from RM Education plc
(see FAQs below for more information).
The RMPrepUSB download includes some executables which are not the
intellectual property of the author or
RM Education. The licensing terms and conditions of these programs are:
Grubinst.exe, grldr and touchdrv.exe– Author: bean123 homepageGPL (see GPL.txt)
QEMU - QEMU was written by Fabrice Bellard and is free software.
HashMyfiles.exe - by NirSoft (licence files included with download)
WinContig.exe. - with kind permission from Marco D. Free for personal and commercial use.
Start_VM.exe - with kind permission from David B. Free with published sources on reboot.pro
Various parts are released under different GNU General Public License version 2-compatible licenses.
These include the GNU Lesser General Public License (GNU LGPL) or permissive licenses such as the BSD license
RMPrepUSB is intended for use on USB Flash memory drive, USB hard disk
drives or other USB storage devices such as card readers.
Press F1 for help and shortcut functions.
format and make bootable a USB drive (follow the steps numbered 1-6 in blue text)
(erase/wipe) a USB drive (best to unplug and re-plug afterwards)
USB drive (or parts of a USB drive) to an image file
image file (or part of an image file) to a USB drive
the grub4dos or syslinux bootloader onto a USB drive
·Test a USB
drive (useful for testing fake USB flash memory drives)
read/write speed of a USB drive
USB drive (for safe removal)
the partition structure of a USB drive (or image file)
after PEBuilder to install your XP PE files to a bootable USB drive.
·Work on hard
disk drives as well as USB drives (by
using the ALLDRIVES command line parameter)
·Create an ext2/3/4 read/write filesystem (as a mountable
file – e.g. casper-rw)
· Emulate booting from the selected USB drive (QEMU = F11) v2.1.707 and later versions have full write access!
· Calculate MD5/CRC32/SHA1 checksum of a file (ALT+F2)
· Overwrite Master Boot Record with default (Win7/Vista) MBR
· Run Disk Doctor utility for disk testing/editing
· Install the WEE bootloader to Track 0 (overwrites MBR)
· Run DiskDoctor (a raw disk editing/testing/data search utility)
· Make all files on a drive contiguous using WinContig
Install grub2 to MBR+following sectors
Note: Red or blue coloured buttons will write
to your USB drive in some way.
Except for the TestSpeed
button, all red/blue buttons will erase, alter or overwrite your USB drive
contents. If you have any important files on the USB drive, copy them to a safe
run these utilities with Administrator privileges or USB drives may not be
accessible and you may get a write error reported!
When you click on one of the Prepare Drive,
Quick SizeTest, TestSpeed, Clean, ImageTool or Info
buttons, RMPrepUSB will call the Windows command line utility RMPartUSB - the exact command line will
be shown to the user beforehand. If you prefer, you can use RMPartUSB in your
scripts or batch files rather than use RMPrepUSB. Type ‘RMPartUSB’ in a Windows
command shell to see full instructions on how to use the utility or read the rmpartusb.txt readme file.
Fig. 1 Note: The button ‘6 Prepare Drive’ uses the settings numbered 1-5.
The two imaging operation buttons (FiletoUSB and USBtoFile) are totally independent of any other settings within RMPrepUSB
(i.e. the NTLDR, FAT32 and all other options have no effect when imaging – a binary image is simply copied to or read from the UFD
and is similar to the dd.exe utility, no additional ‘tweaking’ is done by RMPrepUSB or RMPartUSB and no extra files are copied afterwards).
The ‘Install grub4dos’ function installs grub4dos to any USB drive and does not call RMPartUSB.
Also note that during operation, both the commands that will be executed and the status are shown at the bottom of the form.
Fig. 2 RMPrepUSB Help form (press
F1 or Help button)
Note the extra functions available using the Function keys!
1.Select the USB drive in the listbox if
more than one is present and either leave the ‘1 Partition Size’ as MAX or change it (e.g. type 512 for a
partition size of 512MiB).
the ‘2 Volume label’ text if you
the ‘3Bootloader Options’ that you want installed onto the new partition
after it has been formatted.
the ‘4 Filesystem and Overrides’.
You may need to experiment with these before you can find a combination that
works. If in doubt use ‘FAT32’ and ‘Boot as HDD’.
you want to, you can copy the contents of a folder (or zip/iso file) to the new empty partition
on the USB drive after it has been formatted by RMPrepUSB. Tick the ‘5 COPY OS FILES’ box if you want to do
this. Note: RMPrepUSB will not place any boot files on the USB drive and it
will not be bootable unless you copy some boot files onto it using this option or by manually copying files over after formatting.
on the blue ‘6PrepareDrive’ button.
WARNING: After a format operation or if Refresh is clicked, RMPrepUSB may select a different drive
in the drop-down list. ALWAYS check
that the correct USB drive is selected before clicking the Prepare button!
finished and before you unplug the USB drive, click on the ‘Eject’ button to
prevent file corruption.
If you are experiencing difficulties using RMPartUSB or RMPrepUSB
when formatting drives as a ‘floppy’ device – try disabling your antivirus software. Some antivirus software (e.g.
Symantec) can interfere with direct access to the drive once it has been
formatted as a floppy drive! Alternatively, disable floppy disk scanning in your AntiVirus options.
Special shortcut keys:
F1 – Help F2 – Open Explorer @ USB drive ALT+F2 will calculate MD5/CRC32/SHA1 checksum of any file CTRL+F2 - run WinContig to defrag all files on selected drive ALT+CTRL+F2 will overwrite the MBR with a default one F3 – Open Explorer @ RMPrepUSB application home folder F4 – Open menu.lst from root folder on currently selected USB drive with notepad F5 – Refresh ALT+F5 or CTRL+F5 - Toggle the mode to allow operation on all types of drives (ALLDRIVES/USB_ONLY) CTRL+Z - Show all sizes of USB drives (inc. > 128GB) v1.735+ ALT+CTRL+F5 - Launch Disk Doctor utility
F6 – Open USBSpeedDP.csv using the spreadsheet app. associated with .csv files F7 – Open USBSpeed.csv using the spreadsheet app. associated with .csv files F8 – Open USBSpeedDP.csv in notepad F9 – Open RMPrepUSB.ini file in notepad F10 – Save current configuration settings to RMPrepUSB.ini F11 - Run QEMU and emulate booting from USB drive F12 – Load user pre-set menu again (if RMPrepUSB.ini file present) ALT+F12 - Install WEE bootloader
If you have the English
language selected, you can press F1to see this hotkey list and then press ESC to close the help form.
There are many other hotkey combinations - these can be seen when you use the menu tabs:
Fig. 3 Drive menu showing hotkey shortcuts
About the COPY OS FILES function
RMPrepUSB prepares a USB drive by
partitioning it, formatting it and placing boot code in the Master Boot Record
(MBR) and Volume Boot Record (VBR, sometimes called the Partition Boot Record
or PBR). However, the USB drive will not boot unless you copy boot
files onto the drive. You can automatically copy files to the root of the USB drive after
it has been formatted by ticking the COPY OS FILES option. If you do not tick
this option then you must copy any boot files onto the USB drive manually
afterwards (make sure you copy the system and hidden files too!).
The latest version allows you to either COPY FILES FROM A FOLDER (yes) to the root of the target drive or EXTRACT FILES FROM A FILE (no) and copy them to the target drive. If you have all your files in a folder and just want to copy the files inside the folder to the USB drive, then choose 'Yes'. If you select a folder, the entire contents of the folder will be copied after the format has completed.
The contents of the selected folder (and all subfolders) will be copied if you choose 'No'.
If you want to EXTRACT files from a compressed file (e.g. an ISO or ZIP file) then choose 'Yes'. If you answer 'yes', and then select a compressed file, such as an ISO file or zip file, the decompressed contents of the file will be copied to the target drive after it has been formatted.
You can ask RMPrepUSB to extract files from an iso,zip,7z,gzip,cab,rar,vhd,lzh,img or ima file after formatting has completed.
Saving your favourite configurations
If you regularly make bootable USB drives or you want to distribute RMPrepUSB to
other users inside your company or friends, together with a source folder
containing your OS files, you can save the RMPrepUSB settings to RMPrepUSB.ini
automatically by pressing F10. Here
is how to do it:
A. Place your source OS files in folders on the C: drive of your hard
Now for each USB configuration:
B. Run RMPrepUSB (you must click cancel if you already have an RMPrepUSB.ini
file present and are prompted to choose a previous configuration) and actually
make your bootable USB drive as you would normally (you do not have to do this, unless you use syslinux,
but it helps to get it right - if you don't actually make a USB drive then
check the contents of the RMPrepUSB.ini file after making it). If you need to
use the install
syslinuxoption, you mustrun through a complete
format/syslinux operation to set the correct Raid/Syslinux options so they are
saved to the ini file correctly when you press F10.
C. (optional) After 'Prepare Drive'
has finished and the file copy has completed, untick the ‘No user prompts’ box
and then click on Install grub4dos and choose the grub4dos options
as you require (this sets the grub4dos option to either MBR or PBR depending on
which one you choose). If you don't need to run grub4dos, then skip this bit as
it is not necessary. If you also want to create an ext2 filesystem, you should use the
Create ext2/3/4 FS button to set those options (though you can cancel after
entering the volume name and size parameters). Now you can tick the ‘No user
prompts’ box again if you don’t want the end user to have lots of prompts.
D. Now press F10 - you should be asked if you
want to append the settings to the configuration file RMPrepUSB.ini. F10
records all the current settings including the MBR or PBR selection used
when grub4dos was run, also any syslinux options and also the ext2 filename/size and appends
them to the end of the RMPrepUSB.ini file as a new entry.
E. You will be asked to input a title (which will eventually appear in the user’s
menu on each first run of RMPrepUSB – see section F below) and then add some text for the user’s instructions:
don't already have an RMPrepUSB.ini file then it will be created for you. You
can press F9 if you want to see it or edit it.
Repeat this (B-E) for all your
different types of bootable OS's.
F. Exit from RMPrepUSB and then restart RMPrepUSB - because an INI file is now
present in the same folder as RMPrepUSB.exe, the user will now see a menu list
when RMPrepUSB first runs and can pick one of the preset configurations.
will not set any options, but choosing a configuration and clicking OK will pre-set
the options which may override any options the user chooses. The user will now
be prompted with the instructions that you previously entered into the
configuration file, e.g.:
G. When the
user clicks on the ‘6 Prepare Drive’ button, they will be prompted to accept or
refuse the SIZE and VOLUME LABEL that was set in the configuration file:
If the user
chooses ‘No’ then the current settings in RMPrepUSB will be used; ‘Cancel’ will
abort the operation.
If you used ‘Install grub4dos’ and/or the ‘Create ext2/3/4 FS’
button, it will automatically run with the correct options that you recorded in
the RMPrepUSB.ini file.
edit the INI file using Notepad to make changes or delete any section – just
press F9. Note that you can hide some buttons and checkboxes if you wish. Here
is an example RMPrepUSB.ini file with only one menu item:
TITLE=Ylmf Live USB
USERPROMPT=Click 6 Prepare Drive to format your USB drive, install grub4dos and
create an Ext2 filesystem named casper-rw for Ylmf
You can now ZIP up all source files and RMPrepUSB files and create a
self-extracting EXE which will extract the source files to the correct location
on the hard disk (i.e. C:\ACME\RMPrepUSB in this case). This is especially
useful if you have the same source files but have different systems which need
different RMPrepUSB options set (i.e. some systems boot with Force LBA set and
some do not - so you can have two configurations but only one set of source
files). Alternatively, you can create a self-installing distribution file
using NSI – see the tutorial on the website for more details.
Note: if your partition is small (e.g. DOS), rather than use preset
configurations, you can also distribute an image instead, using the
'USB->File' function (make sure the USB partition size is as small as
possible - just big enough to hold the OS files to keep the image size small)
and use the PALL option.
The RMPrepUSB PDF file (press F1 and then OK to view it) has a more detailed explanation of the steps above and includes screenshots too.
How to boot to an Operating System
RMPartUSB only partitions and formats the drive. You must copy
over the boot files to make a bootable disk. RMPrepUSB can copy these boot
files to the USB drive if you use the COPY FILES folder and tick the Copy check
Hint: If the boot
files are present but your PC is not booting correctly - check your BIOS menu
options! Some BIOSes have an option to boot a USB drive as a ‘Fixed Disk’ or a
‘Removable Disk’. Try different BIOS settings if you are having difficulty
getting your USB drive to boot!
Here are some quick
tips on what boot files you may need to boot different Operating Systems:
Required extra boot files
requires IO.SYS (or MSDOS.SYS depending on the version used) and COMMAND.COM in
order to boot. You must obtain these files from somewhere (e.g. a DOS floppy
boot diskette?).Simply copy these files
onto the USB drive after you have formatted it using the MS-DOS option, by
using the COPY FILES option to point to where you keep these MS-DOS boot files
and tick the Copy checkbox.
requires the files KERNEL.SYS and COMMAND.COM (which may be renamed in some versions) in order to boot. The latest
version of RMPrepUSB includes the few essential boot files in a FreeDos folder,
so simply use the COPY FILES option and select the FreeDOS option in RMPrepUSB.
WinPE v1 and XP
require many files to boot, but the first file is NTLDR. If you want to boot to
BartPE, see Q24 below.
WinPE v2 and v3
and Vista and Windows 7 require many files to boot, but the first file is
BOOTMGR. For instance, just copy all files from a Vista or Windows 7 bootable
DVD to the USB drive after formatting using the WinPEv2 (bootmgr) option in RMPrepUSB.
booting will first look for the files LDLINUX.SYS and a SYSLINUX.CFG file. Many
other files will also be required. If you are using isolinux, use the Install SysLinux
RMPrepUSB option and then after the files have been copied over, rename
isolinux.cfg to syslinux.cfg. Note that when RMPrepUSB installs syslinux it uses the -fma switches, so as well as the PBR boot code being changed, the MBR boot code will also be changed. If you want to also boot to grub4dos, install grub4dos to the MBR after running syslinux.exe. You can then boot to grub4dos, and then to syslinux by using chainloader (hd0,0)+1 to load the syslinux PBR bootstrap code.
booting will first look for the file GRLDR. RMPrepUSB will ask you if you want
it to copy this file after it has installed the boot code. After that it will
look for a \menu.lst file. Note that the version of grubinst.exe is not the
normal v1.1 version, it is a ‘homebrew’ version (I have called v1.2) which
has been specially modified to work on more systems/BIOSes than the old 1.1
version. The grldr file is recent ‘chenall/tinybit’ version but you can change
it for any version you like by overwriting the file.
If you want to use a different version of syslinux or
grub4dos, place your own versions of syslinux.exe, (grubinst.exe) and grldr
into the same folder as RMPrepUSB and overwrite the ones provided.
Explanation of the Override options
The most complex part of RMPrepUSB is in selecting which overrides (if
any) to use. The reason that there are so many choices is that different BIOSes
behave in different ways. A USB Flash Drive (UFD) that is formatted normally and contains MS-DOS boot files may boot as an A: drive on
one system, but boot as a C: drive on another system. If you change the BIOS
Setup menu options on the same system, it might then boot as an A:
drive. On yet a third system, the same USB flash drive might not boot at all!
In addition, some BIOSes will not boot from a UFD at all if the physical
drive size is greater than 512MB – or – some BIOSes may not boot from a UFD if
the volume size is over (say) 1.3GB.
If you wish to boot from a UFD or USB hard drive, you may need to
experiment with the settings below. You may find that one group of settings
will work for one system and a different group of settings will work for
another system. If using UFDs, always try a 512MB USB flash drive first before
you move on to larger UFDs – some older BIOSes will only work with small UFDs.
Boot as FDD (A: no MBR)
This option will format the drive with the chosen filesystem format
option (FAT16\FAT32\NTFS) - the
USB drive will have no partition table just like a floppy disk. The first sector of the USB drive will
typically contain the operating system boot code. This option is usually used
for an MS-DOS or FreeDOS drive that you wish to boot as a large floppy drive
(i.e. they will boot to the A: prompt).
You can also select the 64hd/32sec option (recommended). If you
de-select the 64hd/32sec option and have FAT32 then the volume boot record will use 255 heads and 63
sectors per track on drives over 4GB - otherwise 64 spt or 32 spt depending on the size of partition.
Note: If you need to boot as drive A:, grub4dos can be used to map the
UFD always as drive A: even if the BIOS tries to boot it as a hard disk. See FAQ 35.
Boot as ZIP (A: with MBR)
This option creates a Master Boot Record and partition table in the
first sector of the drive. The Volume Boot Record code that is written to the
drive will be suitable for booting MS-DOS or FreeDOS as a floppy drive. In
addition, a drive geometry of 64hd\32sectors will be used (if possible).
If you wish to boot the USB drive as a hard drive then untick this
option or tick the 64hd\32sec option.
‘Force use of LBA calls’ can be used with this override, but ticking the
64hd/32sec override will de-select the ZIP option, as the ZIP option will add
the 64hd\32sec override.
Note: Some ZIP drive specifications define the first three entries in
the partition table as unused and the fourth partition table entry is used,
however this partition arrangement is not recognised by Windows and such a partition cannot be accessed by Windows Explorer.
Only the first partition of a removable drive can be accessed by Windows OS’s
(unless a special driver is installed).
Boot as HDD (C: 2PTNS) - Recommended to try first!
This option simply adds a second, small hidden partition entry to the
partition table. Some BIOSes will treat a USB drive as a hard disk if it sees
more than one partition table, because the ‘specification’ of a ZIP drive
(super-floppy) is that it must only have one partition (thanks to ‘online’ of www.boot-land.net for this discovery). If you want to boot a system from a USB drive as a
hard disk, set this option and untick the ZIP option. You can try either the
‘Force LBA’ override or the 64hd\32sec override with this option.
Note: If you want to boot a USB drive as a hard disk and this option
does not appear to work, try re-partitioning again but leave all the USB-FDD, USB-ZIP and USB-HDD options
Forcing the use of LBA calls
(only use if boot problems)
This option sets the end
Cylinder/Head/Sector values in the partition table to their maximum value of
1023 (3FEh) cylinders, 255 heads (FEh) and 63 sectors – even if the partition
size is under 8GB. If BIOSes read a drive partition table and see that the CHS
value is the maximum, then the BIOS may use a sector translation of 255 heads
and 63 sectors per track. In addition, partition and volume boot record boot
code will use LBA Extended Int 13h BIOS calls if it determines that the CHS
values are set to the maximum. This also may help to successfully boot an
operating system from a USB drive.
This option cannot be used with the 64hd\32sec option as they are
Use 64hd/32sec if possible
Instead of creating a partition table using the default drive geometry
of 255 heads and 63 sectors per track, this option will use 64 heads and 32
sectors per track which is the most compatible setting for USB-ZIP
(large-floppy) booting. If the partition is too large to use 64\32 geometry,
then 128\32 will be used instead and then 255/32 and then 255/63.This option is recommended for ZIP (large
floppy) booting and FAT16.
ver 2.1.639 and later - If FAT16 is selected and this 64/32 option, then a partition type of 06 will be used instead of 0Eh. If you need to use DOS6.22 or an earlier DOS OS that is not compatible with later partition types, use FAT16+32/64. DOS 6.22 will not boot with a type 0E partition type.
BartPE to USB tick box
This tick box should
be used if you want to boot an XP/WinPE v1 based OS such as BartPE from a USB
drive. It can be used to prepare PeBuilder BartPE files or other XP-based boot
CD files such as those used on Asus EeePC XP Recovery DVDs. You can only tick
this box if you have selected the XP booot option and have also ticked the COPY OS FILES tick box.
Function: After RMPrepUSB has partioned and formatted the USB drive, it will copy
over the files in the COPY OS FILES folder and then run the RMPrepUSBXP.cmd script file (or the
rmprepusbxp_german.cmd file if the german language is selected). This script
performs a similar task to petousb.cmd, on the USB drive only it...
1. Copies \i386\setupldr.bin to \NTLDR
2. Copies \i386\NTDETECT.COM to \NTDETECT.COM
3. Renames the \i386 folder on the USB drive to \MININT
4. Copies all files and folders in the RMPrepUSB folder PEtoUSB from your hard disk to the root of the USB drive (this
folder is normally empty unless you copy extra files to it first).
A typical usage would
be to use PeBuilder and set the Builder source to your XP SP2 or SP3 install CD
and the Builder output to BartPE and
the Media Output to None and then press the Build button. After the build has
finished, copy any extra files you want to add to the USB drive (e.g. portable
apps) to the PEtoUSB folder which is in the RMPrepUSB folder on your hard disk
(optional) and then use RMPrepUSB
and set the COPY OS FILES folder to the BartPEISO folder path (e.g.
C:\pebuilder3110a\BartPE) and tick the
XP, NTFS and BartPE options. This should make a BartPE bootable USB drive.
To partition and format a non-USB drive, you must run RMPrepUSB using the command line ‘RMPrepUSB
ALLDRIVES’ which must run with Administrator privileges. RMPrepUSB will then
list all drives rather than just the USB drives. You could save your hard disk MBR
using USB->File in this way. WARNING:Do not accidentally wipe the wrong hard disk! You can also create a
Windows Shortcut for this and specify ALLDRIVES as a parameter (but take
care!). There is an option in the Start Menu to run in the ALLDRIVES mode, or alternatively simply type Alt+F2 to toggle the mode on and off when running RMPrepUSB.
FreeDOS and MS-DOS boot as A:
Size=500 Boot.as.FDD 64hd\32sec FAT16
Size=500 Boot.as.ZIP 64hd\32sec FAT16
If either of these
work, try using MAX size and/or FAT32
Ensure BIOS boot
option for USB is set to ‘Removable Drive’ and not ‘Fixed Disk’
BartPE, WinPEv2\v3, FreeDOS and MSDOS boot as
Ensure the BIOS boot
option for USB is set to ‘Fixed Disk’ and not ‘Removable Drive’
Try also various
combinations of these options. Note that one setting may work for one computer
but not for a different computer! Try adding the ForceLBA option if you have
Testing your BIOS (experts only – not in the ‘Lite’ version)
Some special MBR files are provided in the TESTMBR folder. These allow you to test how your BIOS ‘sees’ a USB
drive when you change various options in RMPrepUSB. Please read the ReadMe.txt file in the TESTMBR
folder for more details. There is also a tutorial on the RMPrepUSB website about this test code. You can also use the grub4dos boot loader shell to investigate how the UFD boots (e.g. type FIND to list all storage devices that grub4dos can see).
Tip for UFD booting as a hard drive
Most UFDs identify themselves as 'Removable devices' but if you want to boot an OS directly from them it is often better if they pretended to be a hard drive. If you have a Lexar or Netac USB Flash drive, obtain the utility BootIt.exe (try a Google search). This
utility has a ‘Flip Removable Bit’ button – click on this and then unplug the
UFD, then plug it in again – if it has worked, your UFD will now always report itself as a
‘Fixed Disk’ rather than ‘Removable Media’. The utility only works with certain
types of UFD controller chips. Many BIOSes will always boot a drive as C: (hard
disk) if the device identifies itself as a ‘Fixed Disk’ rather than ‘Removable
Media’. You can also create and access multiple partitions on the USB Fixed drives under Windows, rather than just the one partition allowed for 'Removable drives'.
To boot a linux
system, use the SYSLINUX option in RMPrepUSB. This will format the UFD as a
FAT16 or FAT32 MSDOS volume and then (after copying files if you tick the file
copy option) will run syslinux.exe on the new UFD volume. The Windows version
of syslinux.exe must be in the same folder as RMPrepUSB.exe.
Syslinux.exe will install syslinux boot code into the volume specified
and place the file ldlinux.sys on
the UFD. Do not delete, overwrite or move this file once syslinux has placed it
on the UFD or the UFD may not boot – it must remain at the same sector position
on the UFD. If you already use syslinux.exe, replace the version in the
RMPrepUSB folder with your version to avoid compatibility issues.
When the UFD boots, it will load ldlinux.sys and look for a syslinux.cfg
file, which can contain a menu and details of which kernel to load. If you have
an isolinux.cfg file, you need to rename this to syslinux.cfg. More information
can be found on the internet about syslinux.
If the UFD fails to
boot after a while, either re-format the UFD using RMPrepUSB again or run
syslinux.exe from the Windows command line (cmd) – e.g.
syslinux –fma F:(where F: is the volume letter of the UFD)
WARNING: take care not to specify your hard disk drive letter or your hard disk
will not boot to Windows!
If you have a linux version that supports a persistent mode, you
can use the Create ext2/3/4 FS button to
create an ext2 filesystem as a file on the USB drive. Typically, for Ubuntu
based versions it will be named casper-rw, be in the root and have a size of at
The full version of RMPrepUSB contains a few different versions of Syslinux. If your OS files require an earlier version of Syslinux, simply copy the version that you require from the RMPrepUSB\Syslinux folder (e.g. v3.86) and overwrite the version in the main RMPrepUSB application folder (press F3 to list the RMPrepUSB application folder in Windows Explorer). The equivalent menu.c32 files are also included in the syslinux folders and these can be copied to your USB drive if required.
If you are installing linux (e.g. Ubuntu or YLMF) and want an ext2 filesystem (e.g. a casper-rw volume), you should create a file of the same name using the ‘Create Ext2/3/4 FS’ button (v2.1.732+).
Note that ext3 or ext4 is much less likely to get corrupted, so I recommend ext3/4 wherever possible.
Installing the Grub bootloader
The ‘Install grub4dos’ button will run grubinst on the selected USB drive and then ask the user if they
wish to also copy the grldr file.
The USB drive should be already partitioned and formatted before you click this
button. If the grub MBR does not seem to be written to the USB drive (because
it does not seem to load grub but boots to DOS) then try the Eject button
before you click on the ‘Install grub4dos’ button (but you will have to copy
over the grldr file manually after re-inserting the USB drive). You will also need a menu.lst file.
You will be given the choice of
installing grub4dos as an MBR or a PBR. MBR will usually work for most systems,
but if you have problems (e.g. flashing cursor on boot) try PBR instead.
A guide on how to use grub4dos is here or there is
also a tutorial here.
To test the USB drive and your grub4dos menu, press F11 to run the QEMU emulator (or SHIFT+CTRL+F11 to run in write protected mode)
Installing the grub2 bootloader
Select the BootLoaders tab - Install grub2 to MBR.
For a typical install just accepts defaults ('Yes'). Otherwise, you can load your own boot.img (MBR boot code) and core.img (grub2).
Installing WEE bootloader (ALT+F12)
To install the WEE bootloader, type ALT+F12. You will then be presented with the default menu (weemenu.txt) which can can edit if you wish. Close the editor and a script will run which will list the weemenu.txt file for you to check and the hard disks that are in the system. You will then be prompted to confirm the installation of wee to the MBR and Track 0 of the disk that was selected originally in RMPrepUSB. Type Y followed by <Enter> to install WEE. Details on WEE can be found in Tutorial #68.
Explanation of how BIOSes boot from a
Most BIOSes require the user to enable USB booting and set the boot
order so that a USB device will boot before the internal hard disk (although
some BIOSes have an F10, [ESC] or F12 key function which will allow you to
choose a boot device from a BBS menu). In addition you can often set the USB speed
to USB 1.1 speeds (Hi speed) or USB 2.0 speeds (Full speed). If you are having
difficulty booting from a USB drive, it is recommended to use a rear USB port,
set the BIOS to USB 1.1 speeds and change the boot order so that the USB drive
is first in the boot menu.
Before you enter the BIOS menu, switch off the system, insert the USB drive and
then switch on the system – then press the F1 or F2 or Esc or DEL key
(depending on your particular system) to enter the BIOS Setup menu. Note: it is
highly recommended that you always switch
on the system with the UFD already connected; some BIOSes do not list the
UFD or provide menu options unless the UFD is already inserted. In addition,
some BIOSes only determine the type
of UFD that is connected on the first cold boot, so if you re-format the UFD
using a different RMPrepUSB option and then re-connect it to the target system,
it will not treat the UFD as a different device type (e.g. USB-ZIP instead of
USB-HDD) unless you first switch off the target system and then switch it on
All BIOSes behave differently, however disk storage devices are always
accessed via Interrupt 13h calls to the BIOS. There are two types of ways to
access a disk device via the BIOS – ‘floppy’ or ‘hard disk’ read or writes. The
BIOS must determine whether to allow access to the USB drive that it detects as
either a ‘floppy’ (which is accessed with Int 13h DL=00h,or 01h for the 2nd
floppy drive, etc.) or a ‘hard disk’ (which is accessed with Int 13h DL=80h, or 81h for the 2nd
drive, etc.). The BIOS has to determine which of these two access methods (DL=0
or DL=80h) to ‘map’ the USB drive to.
Once a BIOS determines how to map the USB device (either as a floppy
device or a hard disk device), it will read the first sector from the USB device (512 bytes) into
memory at address 07C0:0000h and then jump to that code. The last two bytes of
the sector must end in the two bytes ‘55h’ and ‘AAh’ or it is not considered to
be valid boot code. When the CPU starts to execute the code that has just been
copied into memory at 07C0:0000h, the BIOS has also pre-set the DL CPU register
to the correct device number (usually either 00h or 80h). The boot code can use
this value in DL to load more sectors into memory from the same USB device.
There are two types of USB drives – Fixed or Removable. The type is
reported by the USB controller when interogated by the BIOS.
There are three ‘types’ of USB drive formats and the BIOS must
try to determine which of the three different ways to access the USB drive:
(floppy disk device)
The BIOS maps the device to ‘floppy’ Int 13h
DL=0. A USB device may be detected as a USB-FDD device if it has a device name
similar to ‘TEAC floppy drive’ and a capacity of 1.44MB, or possibly if it has
no valid partition table. The device does not need to be formatted as 1.44MB,
you can have a 1GB FAT16 UFD with no MBR.
A BIOS maps the device to ‘hard disk’ Int 13h
DL=80h. A USB device may be treated as a USB-HDD device by the BIOS if it has a
partition table and has more than one partition entry in that partition table.
If only one entry exists the BIOS could treat the device as a USB-ZIP drive or
a USB-HDD drive. Sometimes a BIOS menu setting can be changed to alter this
behaviour. If the USB hardware device type is reported as a ‘Fixed Disk’ type
by the USB device controller chip, then most BIOSes will always treat that USB
device as a hard disk and use DL=80h.
A BIOS maps the device to ‘floppy’ Int 13h
DL=0. A USB device may be detected as a USB-ZIP device if the drive has a
partition table containing only one entry. The BIOS may also require the device (not partition but physical device)
to be under a certain size (e.g. 512MB or less) or have values in the partition
table of 64hds\32secs. These conditions vary from one BIOS to the next!
In addition, when a BIOS boots from a device as
a USB-ZIP device it does NOT load the first sector MBR code (LBA 0) into memory
– instead the BIOS loads the Volume Boot Record code directly into memory and
jumps to it by reading the single entry in the partition table to find the
start position of the partition (a USB-ZIP drive can thus only contain one
partition entry). The BIOS then maps the USB drive to the Int 13h DL=0
callBUT it will always adds the partition start address to any access. Thus a BIOS Int 13h DL=0 call to read
cylinder 0, head 0 sector 1 (LBA 0) will actually read the first sector
of the partition. The real sector 1 (LBA address 0) cannot be accessed at all.
For instance, say the USB-ZIP drive has a partition table with a single entry.
The partition table entry indicates that the partition starts at sector 32,
then the BIOS would load sector 32 into memory and start to execute the code
there. Any attempt to read a sector at CHS 0\0\1 (LBA 0) via a floppy Int 13h DL=0 call (or Extended Int 13h
call) from that point onwards, will actually read sector 32. If the boot code
attempts to read CHS 0\1\1 (LBA 32) it will actually read the sector located at
CHS 0\2\1 (LBA 64) as the BIOS will always add the partition start address on
to any access. In this way, the boot code located at the start of the partition
is identical to that found on a floppy disk which has no MBR or partition
Some BIOSes do not support this type of booting
and may always boot a USB-ZIP device as a hard disk (i.e. map the USB device to
respond to Int 13h DL=80h calls) if they see a valid partition table and MBR.
The difference between a USB-ZIP device and a USB-HDD device is very small,
both have a master boot record and a valid partition table, however a USB-ZIP
device should contain partition boot code that expects to be booting from a
‘floppy drive’ (DL=0) whereas a USB-HDD device should contain partition boot
code that expects to be booting from a ‘hard disk drive’ (DL=80h). Many modern
BIOSes contain a special menu option to change this behavior.
About‘Fake’USB Flash memory pen drives
See Tutorial #7 - There is a large worldwide problem with ‘fake’ or counterfeit USB flash
memory drives being sold via web auction sites and markets, etc. These USB
drives often contain faulty memory chips and appear to be larger than they
really are. For instance, a ‘fake’ USB drive may be sold as being 16GB and the
size reported by Windows may indeed be approx. 16GB, however it may be made
with only 2GB of flash memory and the memory chips themselves may be faulty. As
you use it, you may not see a problem until you fill it with more than 2GB of
files. Then you may lose all of your previous files and the drive may
become ‘unformatted’ and totally corrupt.
If you suspect you
have one of these fake USB drives (or even if you don’t!) run the Quick Test
function in RMPrepUSB or use the program H2TESTW.exe (English and German languages are available in
H2TESTW). Here is a quick summary of these two utilities:
·RMPrepUSB - QuickTest – Very quick but destroys all data on the USB
drive. It is not a thorough test and will not detect the odd bad block or corrupt
memory cell. Recommended for checking if you have a fake ‘undersized’ UFD as
it is very quick.
·H2TESTW – Non-destructive (fills the USB pen with large files which can be
deleted by you afterwards). It is very slow!!!! Tests every byte except for areas that are
‘filled’ with the files that are already on it (so best to format it before
testing so that it is empty).
There are also other
utilities available such as the Russian Check Flash (chkflsh).
Download and run the file English.bat for
the English version of this very useful program.
The top Menu Bar (in English only) contains functions that are also available by using a key shortcut (as listed in the F1 Help screen) but it also includes some extra functions which are not listed in the F1 Help form.
The list below explains what each of these menu functions do (in the latest Beta version):
Explore RMPrepUSB Installation folder F3 - Opens Windows Explorer at the folder where RMPrepUSB.exe is currently located
View Speed Test results (USBSpeedDP.csv) F6 - Opens the speed test results file which contains decimal point using whatever application is associated with .csv files (e.g. Excel or Calc)
View Speed Test results (USBSpeed.csv) F7 - Opens the speed test results file using whatever application is associated with .csv files (e.g. Excel or Calc)
View File Information Ctrl+I - inspects an image file and displays it's contents in hex bytes. If the first 512 bytes is recognised as an MBR or PBR then extra values are also interpreted
Boot from ISO file using QEMU Emulator Ctrl+F11 - User can select an ISO file and optionally create a virtual hard disk and then boot QEMU from the ISO (for instance you can install XP to a virtual hard disk using this option)
Make grub4dos ISO from Drive - this makes a bootable ISO file from your grub4dos bootable (USB) drive. It will ask for a volume label and ISO filename and then make a grub4dos bootable ISO from the contents of the selected drive. To make bootable WinPE ISOs, add oscdimg.exe (see Tutorial 83 to get it) to the RMPrepUSB\QEMU folder.
Boot from Virtual HDD image using QEMU emulator Shift+F11 - Boot from a previously installed virtual hard disk image (for instance, you can install linux to a virtual hard disk using Ctrl+F11 and then boot to the hard disk at any time later using Shift+F11)
Create a 1.44MB MS-DOS Floppy Boot Image - Extracts an MS-DOS boot image from a Windows DLL file present in your Windows OS and creates an IMA file
Get File MD5/CRC32/SHA1 (Alt+F2) Ctrl+C - Runs NirSoft HashMyFiles.exe on the chosen file to display it's MD5 and CRC32 and SHA1 values
Exit RMPrepUSB Ctrl+X - Exits RMPrepUSB and saves the current user settings to the Windows Registry
Edit grub4dos menu (Menu.lst) F4 - Load the file \menu.lst into Notepad from the currently selected drive
Edit Speed Test Results (USBSpeedDP.csv) F8 - Loads the file USBSpeedDP.csv intp Notepad from the RMPrepUSB installation folder
Explore Drive F2 - Opens Windows Explorer at the root of the currently selected drive
Refresh Drive List F5 - re-detects all drives and repopulates the drive selection list in RMPrepUSB
Test Drive using QEMU Emulator F11 - Emulates booting from the selected drive using QEMU, a virtual hard disk size and the amount of memory available can be entered by the user first. During emulation the drive will be dismounted from the hots Windows session.
Run QEMU (write-protected) Shift+Ctrl+F11 - same as above but runs QEMU in snapshot mode. Writes to any file will not actually work.
Make All Files Contiguous Ctrl+F2 - Runs WinContig on the selected drive. First only .img, .ima and .iso files are made contiguous, then all files on the drive are made contiguous. If there is not enough room to make all files contiguous, the WinContig app will remain for the user to see which files were not made contiguous.
Launch WinContig Shift+F2 - Runs WinContig and selects the currently selected drive. This allows the user to run WinContig manually.
View Drive Information Shift+Ctrl+F2 - Reads and displays the user selected drive sectors. If an MBR or PBR is read, some data values will be interpreted for the user. If LBA 0 is requested then RMPrepUSB will try to interpret as an MBR or if this fails, a PBR. If LBA > 0 requested, it will try to interpret it as a PBR if it has valid data (v2.1.743c or later).
Format Volume (using Windows) Ctrl+F - This brings up the Windows Format drive Dialogue box. Only for use if RMPrepUSB fails to format a drive or if you want exFAT.
Note: If the device has no MBR or partition table, Windows will format the device as a floppy disk. If the device has an MBR and partition table at the time of formatting, Windows will format the device as a hard disk and it will have an MBR and partition table after the format has finished. If you format as exFAT it will not have a BOOTMGR boot sector unless you run Bootsect.exe on it afterwards. Use the RMPrepUSB exFAT option to format as exFAT bootable.
Disk Manager (diskmgmt.msc) Ctrl+K - This brings up the Windows Disk Manager MMC. Useful to assign drive letters to a mounted drive (NTFS formatting in RMPrepUSB will not work unless the drive has a drive latter assigned by Windows).
DiskDoctor Alt+Ctrl+F5 or Ctrl+D - Launches the RMPrepUSB Disk Doctor application for editing, examining and testing a disk drive.
Edit Disk Signature Ctrl+T - Reads and displays the disk signature of the currently selected drive and allows you to write a new one.
Clear ReadOnly Status - Runs Diskpart to clear the read-only attributes on the currently selected disk and drive letter.
AutoMount Drives (changes Registry) Ctrl+L - Runs the Windows command Mountvol /e to enable automatic mounting of new volumes
Set Windows Accessible Partition Ctrl+O - Allows the user to set any one of four primary partitions on USB Flash drive as the Windows accessible partition.
Install grub4dos Ctrl+G - installs the grub4dos bootloader and copies over the grldr file (same as clicking the Install grub4dos button)
Install Syslinux Ctrl+S - installs syslinux to the currently selected drive using the version of Syslinux.exe present in the RMPrepUSB installation folder
Install WEE Ctrl+W - installs the WEE bootloader to the currently selected drive. The WEE menu will be presented in Notepad to the user first so that it can be changed as required.
Install Std MBR Alt+Ctrl+F2 or Ctrl+B - installs the standard Win 7 MBR boot code to the selected drive. The Disk Signature and partition table are not changed.
Install MSDOS Bootloader (FAT16 only) - calls RMBootSect.exe to insatll the MS-DOS FAT16 bootcode to the Partition boot record
Install BOOTMGR Bootloader - calls RMBootSect.exe to install the Vista/Win7/8 bootloader to the Partition boot record which loads bootmgr
Install NTLDR Bootloader - calls RMBootSect.exe to install the XP bootloader to the Partition boot record which loads ntldr
Install grub2 to MBR - loads grub2_boot.img and grub2_core.img from grub2 folder in the RMPrepUSB application folder. You can specify your own .img files.
Note: To install the grub4dos bootloader on an exFAT volume, format the drive using the WinPE+exFAT options and answer Yes to the prompt after clicking Prepare Drive. Do NOT use the 'install grub4dos' button. The MBR should be the standard MBR.
Edit User Config Menu (RMPrepUSB.ini) F9 - If present, this will load the User Configuration menu in Notepad.
Save Current Config to RMPrepUSB.ini F10 or Ctrl+F9 - Appends the current configuration to the end of the ini file.
Load a User Configuration F12 - loads the User Configuration menu and allows the user to select a different preset user configuration
Use ALLDRIVES Mode Alt+F5 or Ctrl+F5 - Toggles ALLDRIVES mode to show or not show non-USB drives (also affects List Large Drives setting - see below)
List Large Drives > 128MiB Ctrl+Z - by default drives larger than 128MiB are not listed by RMPrepUSB - this will toggle this filter
Minimize Desktop during Operation Ctrl+P - Windows may hide some dialogue boxes during operation of RMPrepUSB and the utilities used by RMPrepUSB. Enable this setting so that all other Windows are minimised when RMPrepUSB is run. The Desktop will be restored once the RMPrepUSB command has finished.
Note: If you specify LARGEDRIVES as a command line parameter, then all sizes of USB drives will be listed (v1.735+) - e.g. RMPrepUSB.exe LARGEDRIVES
Quick Help + Hotkeys F1 - Shows the Usage and Hotkleys help form User Guide (PDF) Ctrl+F1 - Launches the User Guide pdf using whatever application is associated with PDF files
Visit the RMPrepUSB website Ctrl+R - Launches a browser to the RMPrepUSB website
Update Check Ctrl+U - checks the RMPrepUSB website for the latest fully released version. Note that this does not check for the latest Beta version.
About Ctrl+A - Displays the version number of RMPrepUSB
Frequently Asked Questions - Please read!
The Q&A's below contain lots of extra useful information and are worth reading...
Q1 – What happens if I don’t tick any of the
A1 – A partition table will be created using a hard drive geometry of 255
heads and 63 sectors per track. Only one partition table entry will be made.
The volume boot record will be created with hard disk compatible parameters.
Q2 – What code is used for the Master Boot
Record (MBR) ?
A2 – The code used is identical to that used by Vista. It includes
BitLocker support so that if you install Vista or Windows 7 onto a USB hard
disk and then enable BitLocker, it should (!!!) work. The MBR will boot both
‘floppy’ USB drives and ‘hard disk’ USB drives.
Q3 – What boot code is used for the Volume Boot
A3 – The VBR code will
vary depending on what filesystem and format options you have selected, as
FAT16 + MSDOS – MSDOS5.0 identifier, looks for IO.SYS, MSDOS.SYS (or WINBOOT.SYS).
Possible Error Messages: Error! FAT16 + MSDOS + ZIP – MSWIN4.1 identifier, with floppy disk
paramters, looks for IO.SYS, MSDOS.SYS (or WINBOOT.SYS). Possible Error
Messages: Invalid system disk, Disk I/O error, Replace
the disk, and then press any key. FAT16 + FreeDOS – FRDOS4.1 which boots KERNEL.SYS (if ZIP
option used then floppy disk parameters are used) – Possible Error Messages: Error FAT16 + BOOTMGR – uses MSDOS5.0 identifier and boot code and
hard disk parameters. Possible Error Messages: Remove
disks or other media, Disk error, Press any key to restart. FAT16 + NTLDR – uses MSDOS5.0 identifier and boot code with hard disk parameters.
Possible Error Messages: NTLDR is missing, Disk error,
Press any key to restart. FAT32 + MSDOS – MSWIN4.1 identifier and boot code which looks for IO.SYS and
MSDOS.SYS (or WINBOOT.SYS). If ZIP option is used then uses floppy disk
parameters. Possible Error Messages: Invalid system
disk, Disk I/O error, Replace the disk and then press any key FAT32 + FreeDOS – FREEDOS which boots KERNEL.SYS. If ZIP
option is used then uses floppy disk parameters. Possible Error Messages: Loading FreeDOS, No KERNEL.SYS FAT32 + NTLDR – uses MSDOS5.0 identifier and boot code and hard disk parameters.
Includes 4 byte PATCH at E6-E9 changed to 90h (NOP). Possible Error Messages: Remove disks or other media, Disk error, Press any key to
restart. FAT32 + BOOTMGR – MSDOS5.0 identifier. Possible Error
Messages: BOOTMGR is missing, Disk error, Press any key
to restart NTFS + BOOTMGR – Vista NTFS boot code. Possible Error
Messages: A disk read error occurred, BOOTMGR is
missing, BOOTMGR is compressed, Press Ctrl+Alt+Del to restart NTFS + NTLDR – XP boot code with 4 byte PATCH at D9-DCh changed to 90h (NOP).
Possible Error Messages: A disk read error occurred,
NTLDR is missing, NTLDR is compressed, Press Ctrl+Alt+Del to restart.
RMPrepUSB uses special modified VBR code which has various tweaks to improve USB booting on different BIOSes. For that reason it is always recommended to format a bootable USB drive with RMPrepUSB rather than any other format utility.
Q4 – How
do I copy a Vista or Win7 OS install DVD onto a UFD and make it bootable?
A4 – Select the BOOTMGR option + HDD (2PTNs). Browse to the OS DVD and
set the DVD drive letter as the file copy path. Tick the ‘Copy’ checkbox. Click
Q5 – How do I copy an XP OS install CD onto a
UFD and make it bootable?
A5 – There is no simple way to do this from an ordinary XP CD and make a UFD bootable. Please
visit www.boot-land.net for more information. If you wish to install
XP onto the hard disk of a PC by booting from a UFD, you can use WinSetupFromUSB (which has a version of RMPrepUSB built in).
If instead, you want to boot directly from a UFD – try BartPE. Use PE-Builder to create a BartPE folder (by taking files from an XP
installation CD) and then select the BartPE output folder in RMPrepUSB and tick
the COPY FILES box and the ‘PE to USB’ box. Also checkout my UBCD4Win
Q6 – Why does my bootable BartPE\WinPE v2
(Vista) UFD boot on one system but not on another?
A6 – These operating systems expect be present on a ‘hard disk’ type of
device which is accessed via Int 13h DL=80h. The BIOS that does not boot
successfully is probably treating the UFD as a USB-FDD or USB-ZIP device and
thus ‘mapping’ the UFD to Int13h DL=00h and treating the device as a floppy
device. It may be possible to change a setting in the BIOS setup menu (e.g.
Emulate USB device as ‘Fixed Disk’) so that the UFD is treated as a hard disk.
You should also try setting the HDD (2PTNs) option and the ForceLBA option.
Also try changing the filesystem (e.g. use NTFS instead of FAT16). Some BIOSes
will treat UFDs below a certain physical size (not partition size) as a USB-ZIP
device, so try a 4GB or larger UFD. Also, try copying the boot files to the
drive before the rest of the files. The best way to do this is to create a
separate folder containing just the boot files (e.g. ntldr, ntdetect.com,
boot.ini for XP, or IO.SYS, MSDOS.SYS and COMMAND.COM for MS-DOS or KERNEL.SYS
for FreeDOS). Also try with and without the 2PTNS option as some BIOSes
work well with this option but others will not boot at all!
If you are using MS-DOS or FreeDOS, you can install grub4dos and
construct a menu.lst file that maps (hd0) to (fd0) or vice versa. This allows
you to boot to DOS as A: or C: by mapping one device to another. However this
trick does not work for other operating systems that load their own disk
IMPORTANT! After re-formatting a UFD, always switch off the target
system, insert the UFD and then switch on the target system. Do NOT just use
Ctrl-Alt-Del on the target system as some systems do not re-detect the type of
UFD on a warm reset.
Q7 – Why does my MS-DOS bootable UFD boot as
drive C: on some systems?
A7 – This will be due to the BIOS mapping the UFD as a hard drive
(accessible via Int 13h DL=80h) rather than as a floppy device. Try the Boot as
FDD and Boot as ZIP override options.
Q8 – My PC seems to treat UFDs as a floppy
device, how can I boot to WinPE v2?
A8 – There are ways to work around this. First try a larger UFD
and use the Boot as HDD option. Please
visit http://reboot.profor other solutions. A typical way is to use Grub or Grub4DOS as a 2nd
stage boot loader which in turn will load the operating system. For instance,
you can boot to a WinPE v2 iso file using Grub4DOS if your BIOS does not
support USB-HDD booting.
Q9 – Where can I ask a question about RMPrepUSB
or ask for help?
A9 – http://reboot.pro – post specific questions about RMPrepUSB
in the Project Forge – USB formatting utilities – RMPrepUSB topic, for other
questions choose the most appropriate forum and start a new topic. Alternatively, contact the author (me) using the Contact Me page.
Q10 – Can I re-distribute RMPrepUSB or use it
as part of a commercial soultion?
A10 – Only with the permission of the author or RM
Education plc (UK). This is because although RMPrepUSB and RMPartUSB are
Freeware and made freely available for private use, it is not free for commercial purposes. Commercial enquiries should be
directed to [email protected] (ask for ClassRoom Technologies dept.). RMPrepUSB and RMPartUSB are the intellectual
property of RM Education plc (www.rm.com). RM may ask you to remove the software or
take legal action against you if these utilities are used for commercial
purposes (i.e. if you are selling it) without permission or without a licence having first been
obtained (and after all, it’s only polite to ask J ). Redistribution without permission from the author is also prohibited.
Q11 – Does RMPrepUSB/RMPartUSB work under WinPE
A11 – Yes as long as MSVBVM60.DLL is present in the same folder! If no USB drives are listed then copy
this dll file from the WINPE_EXTRA folder to the same folder that RMPrepUSB.exe is
located in. Most functions will work except perhaps the folder browse button in
RMPrepUSB – you may need to type the folder path in manually.
Q12 – How can I use RMPrepUSB in my
A12 – You cannot, but you can use RMPartUSB. Type ‘RMPartUSB’ in a
Windows command console window for help. RMPartUSB uses a command line and
returns an errorlevel after completion. You can also use the LIST, GETDRV and
FIND commands to find the drive number of a USB device. Tip: RMPrepUSB shows
the exact command line that it uses to run RMPartUSB. For instance, you can use
RMPartUSB in a cmd script to detect the presence of UFDs, their drive letters
and partition and format them.
Q13 – Sometimes after running RMPartUSB,it returns a large negative error number –
A13 – This has been observed to occur when using Windows 2000 or when
terminating the RMPartUSB command console window before RMPartUSB has itself
terminated. For instance, if you click the USBInfo button in RMPrepUSB and then
terminate the shell windows that is displayed by RMPartUSB, RMPrepUSB may
report this error message. The reason is unknown.
Q14 – I used RMPrepUSB to format my UFD and
make it bootable but there are no files on it and it won’t boot?
A14 – RMPrepUSB does not copy any boot files. Microsoft boot files are part of the operating system and
cannot be distributed. You can obtain them if you are licensed to do so from
CDs or DVDs or other sources, or use Freeware like FreeDOS (included in the RMPrepUSB application folder - press F3 to view).
Q15 – I have set the USB partition size text
box to 500 MB, how do I set it back to the maximum size?
A15 – Type ‘MAX’ in the Size text box or click on the Refresh button.
Q16 – RMPrepUSB reports an error when it runs
but I know the UFD is good – why?
A16 – Under Vista or Windows 7 you must right-click on RMPrepUSB.exe and
choose ‘Run as Administrator’. Later versions contain manifest files so this
should not be necessary and you should be prompted for permission to let
RMPrepUSB run with Administrator privileges.
Q17 – The Prepare Drive button does not seem to
work under Vista – nothing happens?
A17 – Try creating a folder at C:\RMPrepUSB – do not use a folder in
special locations like the Desktop or My Documents as these may have special
limited access rights under Vista/Win7.
Q18 – I used RMPrepUSB/RMPartUSB and now
something is wrong with my USB pen and I can’t seem to access it.
A18 – Try the CLEAN and QUICKTEST option. If it tests OK, try to re-format
it to a smaller size (e.g. 512MB). If that looks OK try a larger or maximum
size. Use FAT16 or FAT32 (but not NTFS). Partition the USB pen to maximum size
and then use H2TESTW to check the USB drive has no errors. If all else fails,
try a different USB format utility.
Q19 – What does the QUICK SIZE
TEST function do?
A19 – Quick size test will check a UFD for duplicate or bad ‘pages’. It writes
to some sectors on the UFD and then reads them back to see if the information
is correct. For example, it would write 0 to Sector 0 (first 8 bytes), then
2048 to the first 8 bytes at the 1Mb point (sector 2048), then 4096 to the
first 8 bytes at sector 4096 (2Mb point), etc. – and then reads back the
‘marker’ values in each of the sectors. This is useful as a quick test of a
UFD. If it passes this test then you should use H2TESTW to run a thorough test
of all bytes. QuickTest is designed to quickly
check a UFD to see if it contains the correct amount of memory chips. If a UFD
fails QuickTest then there is no need to wait hours for it to be tested using
H2TESTW or ChkFlsh as you know it will fail. QuickTest will also report the
maximum usable size of memory in the UFD so you can reformat it to the correct
Q20 – I ran QUICK SIZE TEST and it
failed – what can I do to fix my UFD?
A20 – First you should realize that even if you manage to ‘fix’ the UFD it will be very unreliable and may fail
(or corrupt the file contents on it) at any time. For instance, you could copy
the latest draft of your new blockbuster novel to it, then copy it over the top
of your master file on your hard disk. Then later you may find out that you
have a corrupted file on your USB drive and have overwritten the original on
your hard drive with the bad versionL – you have been warned!
One way to ‘fix’ it is to partition the UFD to a lower volume size.
RMPrepUSB or H2TESTW will usually give you a clue as to what the maximum usable
size might be. When you have decided on a size, proceed as follows (e.g. you
have a 4GB pen but think only 1GB is usable).
1.Use RMPrepUSB to partition and format the UFD –
use FAT32 or FAT16 rather than NTFS as accessing an NTFS filesystem that has
errors or bad blocks can ‘upset’ Windows and lead to hangs/crashes. Set the
size of the partition as required. Start low – e.g. 800MiB.
2.Run H2TESTW to test the new volume.
3.If the test passes, increase the size in step 1
– e.g. 900MiB and repeat steps 1 and 2 until H2TESTW fails. Then reformat with the previous 'good' size.
Q21 – I started to use QUICK SIZE TEST and H2TESTW
and at first I just got a few errors reported from my 4GiB UFD, but now I get
write errors and the system seems to hang for ages during testing.
A21 – This is a typical symptom of cheap or ‘fake’ UFDs that have been
constructed from faulty memory. The memory may be multiply mapped (e.g. 1GB
mapped 4 times so it appears as 4GB) and the controller bad block management
probably has not been set up properly. Error correction may not even be working
correctly and the memory has probably not even been tested thoroughly by the
UFD manufacturer. Everything may appear to be OK as long as you don’t use more
than 1GB of the UFD, after that files will begin to get corrupted. In addition,
more memory ‘pages’ may fail due to the stress of testing (or normal use) over
time. If a UFD sector write fails, the PC can hang/freeze for many
minutes on each sector write operation – be patient or pull out the UFD to make
it fail quickly.
A UFD from a reliable make and source (Netac, Kingston, Lexar, etc.) can
be tested many times without any problem.
Q22 – I have tested my UFD with
RMPrepUSB and H2TESTW and it is fine, but after a week or so I get corrupt
files or Windows wants me to reformat it and thinks it is faulty. If I
re-format it then all is well until a few days later – is the UFD faulty?
A22 – Are you using the Windows SystemTray ‘Safely Remove Hardware’ icon
and ‘ejecting’ the UFD before pulling it out of the USB port? When Windows sees
a FAT filesystem, it loads the FAT tables into system memory. Any changes made
to the files on the UFD will also cause the FAT tables in Windows memory to be
updated – BUT NOT ALWAYS THE FAT TABLES ON THE UFD ITSELF! So if you simply
pull out the UFD, the FAT tables on it will not have been updated. By using the
‘Safely Remove Hardware’ feature, you cause Windows to write all the new FAT
table changes to the UFD. This is particularly important if your UFD appears as
a ‘Fixed Disk’ to Windows and not as a ‘Removable Disk’. You can check to see
if caching is used by right-clicking on the UFD drive in Windows Explorer and
choosing Properties – Hardware – Properties – Policies. Even if it is set to
‘Quick Removal’ on your PC, you should always use the ‘Safely Remove Hardware’
icon on other PCs - so get into the habit and always do it!
If your UFD is formatted with NTFS, again always use the ‘Safely Remove
Hardware’ icon before pulling out the UFD. The danger is that Windows can write
or read to the UFD at any time, and pulling out the UFD at exactly the same
time can lead to data corruption.
If you are still having problems, try the UFDs which have ‘Ultra Stable
Technology’ (e.g. Netac) or similar. These UFDs employ a buffering scheme which
prevents corruption due to power loss when a UFD is pulled out during write
Q23 – I am having trouble getting some systems
to boot. A USB flash memory pen works on one system but not on another. Some
pens work on one system, but a different pen with an identical image does not
work on the same system! What is going on?
A23 – This is a
typical problem and it all comes down to the BIOS. Read the explanation above
about how BIOSes boot USB devices. Here are some issues that have been observed
with some BIOSes:
The BIOS will not attempt to boot any USB
device over 512MB – the USB pen LED will not even flash during system POST
as no read request is ever made!
The BIOS will not attempt to boot any USB
device over 1GB.
The BIOS will treat any USB device under
xxx MB as a USB-ZIP device, and any device over xxx MB as a USB-HDD
The BIOS will treat any USB device as a
USB-ZIP and always boot it as a floppy device
The BIOS will treat any USB device as a
USB-HDD and always boot it as a hard disk device
The BIOS will boot a USB-FDD formatted
device that has no MBR or partition table, but will not boot a USB-ZIP or
The BIOS will boot any device with only a
single partition table entry in theMBR as a floppy device, but will boot a device that has two
partition table entries as a USB-HDD device
The BIOS setup menu can be use to make the
BIOS always treat a USB device as a ‘Removable’ device (USB-ZIP) or a
‘Fixed Disk’ device (USB-HDD) depending on user choice.
The BIOS looks at the Volume Boot record
to determine type of device (e.g. if it sees MSWIN4.1 then it treats the
device as a USB-ZIP device).
Partition parameters – if the partition
has 32hds and 16 sectors per track then treat it as a USB-ZIP, if 63
sectors then treat it as a hard disk.
If the end cylinder is 1023 (max) then
treat it as a hard disk.
You format the same USB pen using
RMPrepUSB and used the same files (you even make an image and re-used that
so you KNOW the USB pen contents are identical), but it seems to sometimes
work and sometimes not on the same PC – it is as if it has good and bad
A BIOS can be made to boot the same device in different ways – e.g.
USB-FDD, USB-KEY, USB-ZIP, USB-HDD – try each in turn and try different ways of
formatting with RMPrepUSB.
Be methodical in your
testing! There are 5 variables to consider FOR EACH TYPE OF PC as below:
2.Physical size of USB device
3.MBR on USB device (there is no MBR on a USB-FDD device or there is an MBR
and partition table on USB-ZIP and USB-HDD devices)
4.Filesystem the volume is formatted with (NTFS, FAT32 orFAT16)
5.Codein VBR (i.e. if the code
expects to access a floppy drive or a hard disk)
The last three (3-5)
are determined by settings in RMPrepUSB, the first two must be changed by the
user. I suggest using a 512MB USB pen and a 2GB USB pen for all testing and
make sure they have activity LEDs so you can see if the BIOS is reading them.
Also use FreeDos for all initial testing because FreeDos can usually boot to
either a ‘floppy’ device or a ‘hard disk’ device without error (unlike some
versions of MSDOS). Try different BIOS and RMPrepUSB options and write down
all results (all error messages – see Q3 above, and if boots as A: or C:).
PC Model and BIOS version (use
latest version if possible!)
USB pen make, model, size
RMPrepUSB options used
BIOS settings used
Result (did the LED flash, any BIOS
messages, any boot messages, A: or C:, etc.)
WARNING:In between each test, always switch
off the system under test each time, then switch it on, then go into the BIOS and check the settings and
that the USB pen is listed correctly. If you do not cold boot or reset, the
BIOS may ‘remember’ the type of USB
drive that was fitted previously even though you have just re-partitioned the USB drive and
changed its format and boot typeusing another computer! Many computers do not
need to be switched off and on again, but some do – if your computer is one
that does require to be switched off and on again and you do not do this, you
can spend many frustrating hours trying to work out what is going on! WARNING: A lot of BIOSes will remove your (previously
added) USB drive from the BIOS drive boot order menu list if you remove the USB
pen before you switch it on again. So always check BIOS boot order every time!Remember, just because one type of system
works with one particular USB pen drive, it does not mean that other systems
will! Have fun and don’t pull all your hair out!
Q24 - How can I make a bootable USB
pen drive with BartPE on it?