I know virtually nothing about the thing, but the best thing I just found in Google said that there should be two entries for each drive under the key HKEY_LOCAL_MACHINE/SYSTEM/MountedDevices; and one should look something like \DosDevices\C: and another like \??\Volume{f757af4d-26f7-11dc-b15c-00a0d1689bf0}. Now for me, I have one of the first kind for each drive from C: to I: and then like forty or many more of the second kind, which I guess is not normal.

Another thing is, I have dual booted Windows with Linux on what used to be my drive D:. Up until now, I though Windows would just consider that drive as disappeared. Now that I see an entry for that in the registry, I find it kind of weird.

What can I do to get the key cleaned up a bit, if anything at all? Can I delete them all and expect Windows to rebuild a new one on next boot?

So many unintended smilies, have to excuse me.

  • 1
    The fact you know nothing about it indicates you shouldn't touch it. What problem do you believe is caused by additional entries existing? You should not modify your registry hive unless you know exactly what you are doing. I can tell you my personal system the same number if not more entries as your system does, and it runs perfect, if you really want to risk it delete the unused entries which might not be easy for you to determine – Ramhound Jan 12 '14 at 22:06
  • ignore it, the few bytes will might save won't be worth it. – cybernard Jan 12 '14 at 22:07
  • @Ramhound Well I thought asking someone who might happen to know would be helpful. The fact is, there are problems with my computers, start up disk checks to be specific, which were not solved by the usual remedies every one was giving. That messed up key was somewhere I could say the problem was coming from. – arsaKasra Jan 12 '14 at 22:16

It's an old method , but you can simply clear these entries with this console command:

mountvol /r

This removes volume mount point directories and registry settings for volumes that are no longer in the system.


I've had several hundred entries there. No problem.

Basically, these entries are created for every drive that your PC has ever seen. It ensures that your USB disk shows up with the same drive letter and other properties, the next time you plug it in. (There are other bits that tell Windows it's a disk, not an USB mouse).

These keys are cross-linked to other keys. Deleting them manually would be a bad idea. I'd have to investigate a safe way of doing it, but it certainly would involve a Windows reboot.

  • I'd really be happy to hear about a safe way to do it. Until then, if I export the key and then delete it, will it be likely that I would have problems on the next boot? – arsaKasra Jan 13 '14 at 8:06
  • I'm not going to spend time investigating it unless there's a good reason to remove those keys. You still haven't provided a good reason (no, random disk problems do not go away by removing unrelated random entries). As for potential problems, Microsoft usually doesn't add code to fix the registry from damage done by deleting random keys. – MSalters Jan 13 '14 at 10:13
  • Oh, sorry. I think I misunderstood. – arsaKasra Jan 13 '14 at 14:55

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.