Sandisk Extreme Pro 128GB USB 3.0 stick not working under Windows 10?

Hi all,

The technical specs say that the Sandisk Extreme Pro was compatible with Windows 10. I tried mine now in 5 different Windows 10 computers and neither was able to use it. It is seen in the hardware and I can see the partition also in the administration, but Windows does not assign a drive letter to it and won’t let me do that manually.

Putting it back to any Windows 7, Vista or XP system it workes flawlessly again.

My problem now: Even if there was a way to get it usable in my own Windows 10 box: I a work a lot at customer sites and used the stick to have my own software available. Obviously, I cannot manipulate around on their computers. So I need a stick that works without installing software or other maipulation of the PC. This used to work wherever I go before Windows 10. My two spare sticks, one Intenseo and one Lexar show, no problems on any of these PCs. This could be either because they are a different brand or because they are 64 and 32 GB sticks and this is 128GB.

So now the question: Is there any way, maybe by re-formatting or re-partitioning under Windows 7 or Linux, to bring the device into a state where it works with Windows 10?


Hi everybody,

I finally found it myself: The stick must gave a GPT partition table to run under Windows 10.

I hope it will now still work under XP…

It’s embarracing to find the solution right after having posted the question, but I ran into it when I removed the partition in Linux’ fdisk program and found commands to write different partition table types…:confounded:

Are you using it to boot a Linux system, and need a FAT UEFI partition together with a Linux partition?  If so then yes you need a GPT partition table.

FWIW It is possbile to boot a Porteus Linux system on a simple regular single partition FAT32 formated stick on UEFI systems.  It does require the system’s Secure Boot option be disabled but that’s it.

No: I just want to be abe to use it, meaning: copy files to and from it.

With an MBR partition table Windows 10 does not accept the stick at all. As I wrote, it shows the partition, but does nor assign a drive letter, and also does not allow me to assign one.

I’ve been using this stick for a while, on probably more than a hundred different PCs with Windows XP and 7 and it always worked. We just rolled out the first Win10 boxes, and so I notced it: Only Windows 10 systems were not able to work with it, not even to re-format or re-initialize it. And I reproduced this behavior with 3 different Laptops and 2 different PCs running Windows 10 Professsional, 64bit.


I have a handful of flash drives, some with MBRs and some as Super Floppies, and they all work in my Windows 10 system.  However my system does not have EFI and none of my flash drives is larger than 64GB.