Windows (Windows 7 Ultimate 32-bit with newest updates installed) keeps showing only 5MB free of my Kingston 8GB flash-drive, but actually there is only ~4.05GB used (some kind of paradox). Here are some screenshots:

My Computer

All items in the flash drive (no hidden files as you see):
Kingston flash drive

All 3 selected items (hidden and regular):
File properties Kingston flash drive properties

Btw I never unplug the drive because I don't need it, I use it only for ReadyBoost and I don't care how much space there is left while ReadyBoost does it's job, I am just interested in the problem or should I say "paradox"...

After I set different cache size for ReadyBoost and it starts to do it's work, Windows reports 3.80GB free while ReadyBoost works in background applying the cache, and after ReadBoost finishes the applying process, Windows shows the wrong free space size again...


After formatting flash drive and re-enabling the ReadyBoost everything is back to normal. So the question is closed and solved (but don't know what was the problem anyways)...

  • What amount of size show on other PC's or OS's? Any kind of hidden files are there/ – avirk Oct 2 '12 at 15:50
  • 1
    Check for hidden files, save the needed data on your desktop-format the usb-copy data back to the usb – KDEx Oct 2 '12 at 15:54
  • @KDEx actually hidden files actually set to be non-hidden :D – Little Helper Oct 2 '12 at 16:57
  • @David Properties window (3-rd) is showing all three files selected – Little Helper Oct 2 '12 at 16:57
  • 2
    If you only selected the radio button to Show hidden files, folders, and drives but left the Hide protected operating system files option checked, try unchecking the latter as well and see if any huge file (or set of files) show up that are taking up the remaining space. – Karan Oct 2 '12 at 17:59

I had the same problem with my 16 GB flash drive. It turn out my flash drive was storing some files in .trashes. You should go the command line and navigate to your drive. Then use the command "dir" to view everything on that drive. You can then remove files manually using "del".

If you prefer to not use the command line, then try UtahJarHead's program.


Download WinDirStat and find your files. It's open source and free. http://windirstat.info/ It will list all of your files in a nice graphical display with sizes so you can see exactly what's taking up your space.

After reading your below comments, your drive is screwed. There's an issue with flash that crops up rarely. Files will be deleted, as in NOT SHOWING, but the space will still be allocated by the drive. If this is the case, the only thing I've ever seen is that it is permanent damage.

Copy your data off, format it, and hope you get the full size returned to you.

  • Oh yes. And empty your recycle bin. – UtahJarhead Oct 2 '12 at 16:52
  • Well, the app shows that there is only 4 GB occupied but shows that flash drive is full too (paradox). Btw recycle bin is empty... – Little Helper Oct 2 '12 at 17:00
  • Read the above edited Answer – UtahJarhead Oct 2 '12 at 20:16

Is this a genuine flash drive from a trustworthy vendor? I'm asking because I once had strange effects like that with a Chinese flash stick that was supposed to have 16 Gig but wasn't fully equipped (essentially what the stick reported wasn't what it had actually on board in terms of memory).

  • I was using this flash drive for backups and it really has 8gigs of memory. – Little Helper Oct 3 '12 at 6:46

Do you have a ton of small files on it? There is an effect with the usage of clusters/allocation unit on the file system. E.g. if the flash drive has a cluster size of 32KB and if you store an 8KB file there, it will still take 32KB because the system can't assign less than one cluster to a file, so in that case 24KB will be marked as used but wasted. Maybe a similar effect accounts for the missing space.

  • OMG, there is a screenshot of the flash drive facepalm – Little Helper Oct 3 '12 at 19:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.