Sandisk Extreme 64GB - make it a fixed drive?

I’ve been tearing my hair out for days trying to figure this out. At least I finally have an answer. Bottom line–do not purchase this product unless is it marked clearly on the package that it is certified for use in Windows 8.

I also want to mention that it is my custom to create all drives as GPT disks, now that GPT is supported properly by all three major operating systems, and all current PCs ship with UEFI boot support. But, to get around the fact that filesystem support across the three platforms is still spotty, the way I set up my 64GB USB drive is with a 200MB EFI boot partition (as per Mac OS X, I think Windows gives the EFI boot partition only 100MB), an 8GB FAT partition that will mount read/write on all operating systems, and whatever the native filesystem is for the OS I intend to install (ext4 in teh case of Linux, NTFS in the case of Windows, HFS+ in the case of Mac OS X).

So, now I have one drive that has to be relegated to file transfer, solely, because it’s not properly made to work in Windows 8, and I don’t want to risk screwing up a careful build, not to mention valuable data, if it happens to get inserted and used by accident.

In my opinion, SanDisk should provide free exchange of any drives that are not Windows 8 compliant.

"In my opinion, SanDisk should provide free exchange of any drives that are not Windows 8 compliant."

Have you written to them to ask that?

BTW I believe SanDisk has stopped making the Windows 8 to Go USB drives.  Too many people complained they didn’t work with their old USB apps that need removable drives. 

Any news on this?

I am looking for a  fixed drive  version for Windows 8.1 To Go too. 

Or, has anyone been able to create a Windows 8.1 To Go using a removable type drive? reynoldsjrmy?

Has anyone else besides nicoyeyo been able to change one from removable to fixed type using Partition Guru PRO?

Am I correct in thinking that the fixed version comes in a packaging with a Windows 8 certified logo? Anyone care to share a photo of the packaging?

Long shot, but anyone with a fixed type 64GB version willing to sell theirs? I am in the UK.

Sadly, I think there’s non yet. Maybe the developers are still finding ways in order to make this happen. <img src=“”/>

 I registered just to say thanks to cryppy for that link.


Finally I’ve turned my SanDisk Extreme 32 GB USB flash drive from removable in to a fixed drive. This is the way.


Karyonix’s – DiskMod - diskmod.sys driver worked for me flawlessly. I could build a Windows To Go usb drive in minutes.


Thanks man!

You do realize that the drive will only appear to be Fixed on systems that have the diskmod.sys driver installed, right?  On systems without the driver it will still be seen as Removable. 


If you put Windows To Go on it does it boot?  

Posts: 1,836

Registered: ‎07-24-2010

Re: Sandisk Extreme 64GB - make it a fixed drive?[ New ]

‎03-08-2015 06:19 PM - edited ‎03-08-2015 06:23 PM

You do realize that the drive will only appear to be Fixed on systems that have the diskmod.sys driver installed, right?  On systems without the driver it will still be seen as Removable. 


If you put Windows To Go on it does it boot?  

I leave my previous post for reference.


I own a 32 Gb SanDisk Extreme USB stick. After several tries, trying to make the usb stick boot with Windows To Go (I have been successfully able to make it fixed with diskmod.sys and created my WindowsToGo stick using Rufus), it failed every single time to boot, only once it showed signs that it would work using MBR partition thype in Rufus and not GPT, but it hanged for 3-4 hours and I rebooted my laptop eventually.


Then, I stumbled upon WinToUSB which has a different approach. It creates a VHD drive on the USB drive and not applying the install.wim with expanded folder structure as every other tool out there do. For the last approach to work one needs a real proper fxed drive. And that is not available for SanDisk Extreme usb drives as SanDisk had a change of heart (poor heart) and reverted all newer drives’ bit and therefore making them removable again and not fixed drives as they were sold once.


So, for anyone’s interest, I have tested Windows To Go using Windows 8.1 Pro on my 32 Gb San Disk Extreme created with WinToUsb and it works amazing.


Of course one could build the flash drive using the VHD method only using Diskpart.exe and imagex.exe, but it’s a pain in the ass. Takes much much longer and several reboots are needed for it to work.


So go on and try WinToUSb !!! Results guaranteed.



An interesting update kukubau.  Thanks.

Hi folks,

My main problem was not just to make the flash drive appear as a fixed disk but making a bootable Windows To Go device for Windows 10 Tech Preview on my Extreme SDCZ80-064G-GAM46 64GB stick.  

After trying everything else possible from various instructions and tools found online, WinToUSB beta 2.1 finally worked for me on my SDCZ80-064G. Be sure to select the VHD installation mode (used a 14GB virtual disk setting). I tried WinToUSB version 2.0 without this new option and it didn’t work. After using v2.1 beta I am now able to run Windows Tech Preview from the Sandisk Extreme on my laptop. First boot to setup Windows TP was very slow but once loaded / configured, not so bad. Each boot using the WTG drive now takes several minutes but response is decent once it’s up and running.

This solution solved my issue. It looks like WinToUSB creates the boot partition (14GB size in my case) and that is marked as a Basic (fixed) disk but other drive partition still appears as Removeable Disk in Disk Management but that doesn’t matter to me. I only want to use it as a Windows To Go workspace. There may be a way to setup additional partitiions (Disk Management won’t let me shrink the volume while running WTG workspace) creating an unbootable partition to use for normal storage but I’ll let others figure that out… Fo rnow I happy having WTG working.

Good luck!

Updating my own post here: FYI, better to set the VHD to max size of your drive if you want most room in your WTG workspace. I have re-built my workspace to consume the entire availabel space (had to start over with WinToUSB). I think if you leave some space unallocated to the VHD, you can use that remaining space as normal flash storage either in the WTG workspace or indelendant of it. It will appear in Windows as removable drive.

Could you please post step-by-step guide on how to apply the diskmod.sys? I’m trying it with 64GB version and W8.1 64bit(and planning to use Rufus), but my last try resulted in bricked OS

Okay, bricked my other computer, Win8.1 64 bit too, just by installing the driver

Did you follow the install instructions on the link given?

Install and use diskmod.sys

Update: For Windows 7 64 bit you need to enable TESTSIGNING before installing Diskmod

Read more:

Ah, it didn’t say ‘Windows 7 and later’, I’ll try again soon then

Used the testmode command and ran the .bat as admin, and got this error. madness

Solved it by partitioning the drive like this


I realized my error of not reading documentation, GPT obviously didn’t work. Created 60GB NTFS part under MBR and installing it atm, I assume that will work so thanks for help

All works,  diskmod.sys is unnecessary , just use WinToUSB 2.1

It’s nice to see so many people saying “THANKS”  to me after helping them out.


Thank you everyone so far for the guidance.

The following solution finally worked for me with a removable drive on both BIOS and UEFI :

  1. Format the drive using Rufus 2.1 (Rufus adds a custom UEFI NTFS loader so that UEFI can boot from NTFS instead of FAT32)
        - MBR partition scheme for BIOS or UEFI computers
        - File system: NTFS
        - Create a bootable disk using: UEFI:NTFS (make sure to toggle advanced options using the white arrow)

  2. Install Windows 8.1 into VHD using WinNTSetup 3.7.7
        - Mount your Windows-ISO and choose “install.wim”
        - Create VHD (fixed or dynamic, both work)
        - Make sure that drive letters are correct
        - Click “Setup” to install

I hope this is helpful to anyone. I’ll add some images later.