Windows 7 keeps losing drive letters

Question

Windows 7 loses its drive letters and I have to keep manually assigning a drive letter everytime I plug in a hard drive, whether it's internal or external.

The only way to get around it is to reinstall Windows 7 but the problem will come back after a few months. We are a PC repair company and plug in many drives during the say and it can be very frustrating having to keep assigning a drive letter every time a drive is plugged in. Windows Updates are turned off so it can't be that.

Any reason why this would have happened?

Answer 1

I think it probably had to do with the windows saving different drive letters for different drives into its registry. The registry keys are: HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices

I guess if you delete the unused entries it may help... but you may as well ruin the system and need a reinstall if you somehow messed up with it..

so there you go...

Answer 2

It may be that since you are plugging-in so many disks, Windows runs out of drive letters.

When that happens, you can assign the drive letter manually from Computer Management / Disk Management.

If you would like to make Windows forget all drive letter assignments, read this carefully:
Change or Delete System Drive Letter via Registry to Remove Conflict.

Answer 3

I'm using CCleaner to keep my registry all nice and tidy, and as a result, it seems to be wiping the drive letter assignment registry items. While this isn't a solution per se, it seems to me that you may be running into something similar since you're a repair shop and may be trying to keep your test systems squeaky with a daily scheduled registry sweep which could be causing the issue.