HOWTO: flip removable media bit on windows 7 x64 - make a removable drive fixed


Jan 20, 2002
After an afternoon of failures I have worked out how to flip the Removable Media Bit (RMB) on usb drives and SDHC cards under a 64 bit install of windows 7.

This is based off the Hitatchi Microdrive trick, but I found a 64 bit compiled version of the driver on some german site. I did not make this driver I just found it.

64 bit Driver here


Part A
First you need to find the name of your USB or SDHC device
run -> regedit -> navigate to:
find the key that matches your device. Right click on the key and click "copy key name"
My SDHC card plugged into a laptop card reader looks like "USBSTORE\Disk&Ven_Multiple&Prod_Card__Reader&Rev_1.00"

Part B
unzip the files above and open cfadisk.inf in notepad.
scroll down to the section [cfadisk_device] you will see the line
%Microdrive_devdesc% = cfadisk_install,IDE\DiskTS64GCF400______________________________20101008

delete everything after the comma so you are left with
%Microdrive_devdesc% = cfadisk_install,
paste your device string starting from USBSTOR\*whatever* into the line just after the comma, no spaces.
you should have something that looks like this
%Microdrive_devdesc% = cfadisk_install,USBSTOR\Disk&Ven_Multiple&Prod_Card__Reader&Rev_1.00
repeat this process for the section immediately below called

If you are so inclined you can name your device at the bottom of the file by editing the text in the quotes in the last line after it says
Microdrive_devdesc = "your device name here"
save the file, you now have a functioning driver.

Part C
You now need to install the driver
Open Device Manager, find your device and chose to update driver.
Tell windows you want to choose your own driver. Point it at your newly saved file.
Windows will bitch and complain that the file is not signed, and not a compatible driver. Proceed anyways.
Once installed you should see the USB device show up as a "Disk Drive"

Note: When I rebooted the first time, windows would not load, this was due to the driver being unsigned. When booting hit F8 to enter the bootloader, and choose to disable driver signing. Alternatively you can disable driver signing by doing the following:

Now type the following
bcdedit.exe -set loadoptions DDISABLE_INTEGRITY_CHECKS
press Enter:
bcdedit.exe -set TESTSIGNING ON
press Enter:

When you reboot, you should find your USB or SDHC device listed as a fixed disk. You can now partition, make it a dynamic disk, install picky programs that wont run on a removable disk etc.
Just dropping a note of thanks for gathering this info.
I had done some research on it, but was not aware that a 64 bit driver had been compiled.

The alternative to this, for those not wanting to disable driver signing on their server, is to backup to a local directory and copy to the USB stick afterwards, but KISS applies.

For a small domain with little data anf no IT staff, changing out flash drives is preferrable to changing out externals.

Looks like you didn't follow the last steps, which disable the sign driver requirement.

Be aware that, in my case, doing this ended up shifting drive letters on a Dell server with RAID-1 SATA, causing it to boot straight to windows repair. I work remotely, so I couldn't play around to get it working properly while my customer was down...
But I followed the last steps. I think it is because my windows is 64bit. is't it?

finaly I signed this drive by a software. and my computer just didn't load. then I uninstalled that driver.
You need to do that bcdedit bit, with admin rights, and reboot before installing the driver.
Regardless, it looks like it causes boot trouble in certain configurations, at least mine and yours.
Just keep in mind that forcing a removable disk to a fixed disk brings with it implications if not removed properly inviting corruption.
I followed the steps and cannot set SD to fixed drive still. Could someone please explain how to bcdedit bit?

Thank you,
When you reboot, you should find your USB or SDHC device listed as a fixed disk. You can now partition, make it a dynamic disk, install picky programs that wont run on a removable disk etc.

Can this approach be used to install Win 7 on a USB drive, such that when the drive is plugged in, Windows will boot from that drive. If not plugged in, the system would boot from the Windows install on a real fixed drive? If so, that would be awesome. :D :D