Running chkdsk on a Drive Allocated to Windows Server Backup

 What

Howto run an chkdsk on a drive not presented with an drive letter.

 Problem

Windows backup was failing and we would run an chkdsk on this drive.. but there wasn't a drive letter mounted to it!

 Solution

Occasionally I see Windows Server Backup throw odd errors pointing to problems with the disk allocated to Windows Server Backup, such as the bizarre “There is not enough space on the disk” – bizarre in that Windows Server Backup is supposed to automagically manage the disk space allocation and tidy up.

The normal course of action would be to run chkdsk /f on the drive, but the drive doesn’t have a drive letter allocated to it. Nor are you supposed to allocate a drive letter to it. The solution? Use the Volume GUID. To find the Volume GUID, type in the following at an elevated Command Prompt:

mountvol

This will return the command syntax for the mountvol command, followed by the existing volumes and their mount points. We’re interested in the Volume GUID immediately above this line: *** NO MOUNT POINTS *** It will look something like this:

\\?\Volume{12345678-1234-5678-9abc-123456789abc}

We now take this Volume GUID minus the trailing slash and feed it to chkdsk, like this:

chkdsk /f \\?\Volume{12345678-1234-5678-9abc-123456789abc}

 This will then allow chkdsk to perform a consistency check and fix of the drive allocated to Windows Server Backup without needing to allocate a drive letter.