Mysterious drive letter on Windows 8.1

Recently I’ve noted a “Q:” drive letter on my computer which I can’t access, giving “Access denied”.

MOUNTVOL gives the following.


I can unmount it using MOUNTVOL /D, but it comes back on reboot.

This volume has an entry under MountedDevices registry key, but I cannot determine where it comes from.

The drive letter does not appear inside diskmgmt.msc, either.

How can I determine where this Volume is coming from?


Drive Q comes from Microsoft Application Virtualization (App-V). You may have a Click & Run Version of Office installaed which internally uses App-V and this is why you see the drive.

You can hide it very easily by importing this .reg file to the registry:

Windows Registry Editor Version 5.00


Source : Link , Question Author : NothingsImpossible , Answer Author : magicandre1981

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