SanDisk Extreme USB 3.0 flash drive WON'T!


After purchasing a SanDisk Extreme USB 3.0 with 16 GB capacity and finding its speed useful, I then bought a 64 GB SanDisk Extreme USB 3.0 flash drive.
But, after using this between the Ubuntu 16.4 and Win XP SP3 OSs, it suddenly WON’T!
Inserting this 64 GB SanDisk Extreme USB 3.0 in either a USB 2.0 or USB 3.0 slot provides the same situation: nothing is registered on both Operating Systems.
I am at a loss at how this, normally reliable, SanDisk flash drive can be re-activated.
After all, I have hardly used it.


You can see if it is displayed on windows device manager,
Go to: Control Panel>System and recovery> system>device manager

You can see the drive there, then you need to re-format it, if its not there then you might want to send the drive back and get a replacement if its still under warranty.


Yes, I can see it there. Funny, that this is visible on USB 2.0 - NOT so on USB 3.0!
Right-click on this, in USB 2.0, then properties results in NOTHING, effectively: no volume name, no capacity; only ‘removable media’ and file system = ‘RAW’.
–> cancelling properties, choosing format results in ‘unknown capacity’, File system either NTFS or FAT - no FAT32 offered.
Please advise what one can do next.
–> I am using Win XP, SP3 - not connected to any internet.
Thank you for rapid reply. No wonder, with such a name!


Further to my message some 20 minutes ago, I would like to ask whether there is some SW tool that’d re-invigorate this 64 GB.


You can also check if the drive is vissible also in disk management, (i dont remember where disk management is located in windows XP) but if its its there you can re format.

To open Computer Management, click Start, and then click Control Panel. Click Performance and Maintenance, click Administrative Tools, and then double-click Computer Management.

If the drive is visible there as RAM then you could format it, you will loose all your data but the drive should be working.

There is also an option to do this under command line but its more difficult for novice users.


Whilst device manager shows “SanDIsk Extreme USB Device”, Disk Management (under Computer Management) in my Win XP shows a listing similar to that in your example.
Although SanDisk is NOT in this list, it is shown as a removable medium/volume in the pane below, where all the media listed above are shown graphically as partitions, some of which are not allocated. Here, SanDisk even has a drive-letter - and, more interestingly, shows that 59.62 GB are “Unallocated”.
I accept that any data on this SanDisk will be lost, but most are already copies stored elsewhere.
–> Normally, in creating a partition here, only NTFS is the file system - on a disk.
–> Would FAT32 be available for partitioning the SanDisk USB flash drive?
It would be interesting to know what the DOS command is as a possible last-resort(?) solution!
Thank you.


The Windows XP format utility is restricted to a 32GB limit when formatting FAT32 (even though the format supports up to 2TB). Therefore your options are using NTFS or formatting FAT32 in a third-party application/OS and hoping it will be recognized. You may want to use a third party tool anyway to format with correct sector size alignment for flash memory (otherwise may lead to lower flash lifespan).

I will say though that I’ve had bad experiences with using 64GB flash drives under XP. Very bad performance (slow transfers), system crashes during recognition and mounting process, and data loss should be expected (every single time you use it). Personally I ditched the 64GB stick and went and bought two 32GB ones.


Thanks for your useful hints, aztekk.
I had been wondering about the 64 GB capacity being a problem with Win XP.
–> Could I not create TWO partitions, each with almost 32 GB, on this flash drive? If Win XP makes them NTFS, so be it. As long as they can be used, then it surely it does not matter.


Technically you can partition a USB flash drive, but Windows will only recognize and mount the first partition. Also you cannot do partitioning on removable storage (at least without flipping RMB descriptor bit) inside Windows.

In other words, not practical.


So, I could use 32 GB of this flash drive on Win XP.
–> Do later Win versions (Win 8 or Win 10) also have this limitation?
–> Could I then use GParted in Ubuntu to create the second partition on this SanDisk?
__(Info for kind helpers: My Win XP is never attached to the Internet. It is my work-horse, using it for scanning paperwork, making photo-albums, etc. “Never change a running system”, as they say! Win 8 & 10 are awfully cumbersome, and I do not want to waste time learning yet another MS GUI, when underneath it is old hat.)
vroom: I would appreciate your giving me that command you mentioned for formatting (up to 32 GB).
Thank you.


I believe the newer versions of Windows are also limited to formatting max 32GB with FAT32. You can use GParted to format the full 64GB with FAT32 and it may work with Windows too. I don’t see the reason for having 2 separate partitions though.

I think the command he was talking about was diskpart, which wouldn’t really work if the drive isn’t shown in the “list disk” output (mine is not). Then you can also not delete the current partition (in XP diskpart) as it will return an error saying you can not perform this operation on removable storage. If the drive is shown in “list disk” then you may be able to use diskpart to partition and format the volume. By the way, diskmgmt.msc works just as well perform format operations as diskpart imo. If you need more functionality use 3rd party tools like GParted.

P.S. I use only Windows 2000 and XP across all of my computers. To hell with the new junk!


Under Win XP, I created a new partition = 64 GB, NTFS. The only trouble was that there was no means of specifying cluster size, presumably default = 4 KB.
–> I’ve looked up tables of cluster-sizes, and see that the usual FAT32 for flash drives is 16 KB.
__A couple of important questions:
–> “cluster size” = the “sector size” to which you refer?
–> Could I change this from 4 KB to 16 KB, thereby achieving ‘correct sector size alignment’?
–> Or should I use GParted to format to FAT32 and, presumably, the 16 KB cluster/sector size?

Where can one find informative articles on flash-memory’s correct sector size and lifespan?


** When clicking on “Reply”, I twice had an error flag. My message, above, remained in an edit pane, although I could see it ‘greyed out’ and labelled with my ID & “Waiting on Activation”. A third attempt, when the this message had been accepted at 22m, proved successful - but the timer re-started. **

Following the partitioning & formatting to 64 GB on the flash drive, on Win XP, I then shovelled a some 16 files = 5 GB on to it, still in the USB 2.0 slot. After transferring and emptying on to Ubuntu, I again plugged it into the same slot. The usual XP clunk sound, followed by automatic opening of window for this media AND a message-pane indicating suitability for USB 3.0.

Then I removed this flashy drive from its USB 2.0 slot and popped it into a 3.0, where I formally DID NOT register. Now, all is hunky-dory.

Save, that is, it has incorrect sector-size.
–> Can flash drive remain as NTFS, but change to ‘correct’ sector-size = 16 KB?

Without the nitty-gritty on matters flash drives, it is a difficult playing field. Offering a link or search suggestion would be appreciated.


The FS’s cluster size has got nothing to do with the sector size of the flash, and you should leave that to default value (you won’t gain any performance over USB 2.0). And as I said I was talking about “sector size alignment” not the actual size of the sectors, which (unless something has changed in recent years) is 512 bytes for USB flash drives. Therefore I don’t think you ought to be too worried as Windows XP should begin sector alignment at an offset which will not cause problems (data written to two sectors which could be fit into one, adding more wear to flash than necessary). But in case it worries you, that the flash chips have changed to 4K sectors then use GParted to do the partitioning.

[quote=“mgb41238, post:12, topic:398323”]
–> Can flash drive remain as NTFS, but change to ‘correct’ sector-size = 16 KB?[/quote]

Again, there is no “correct” cluster size but if you were to change this you would have to re-partition.

Those would be some really boring articles. :­)
I don’t read any such stuff recently, but I am sure you will find some information if you google “SSD sector size alignment”, if you’re interested. Maybe also “cluster size vs sector size” since it confuses you.


I’d already been thinking of getting an SSD, but heard -ve comments on lifespan and handling.

Is this of interest to you? A cursory glance seems worthy of an night-cap read.

Many thanks for your patience and comprehensive support.