A Hyper-V GRT enabled backup of a remote Windows 2012 Hyper-V guest, will fail with the error below, if the Backup Exec 2012 server is running Windows 2008 (not R2) AND the Hyper-V guest is configured with .VHDX disk(s). Once this error occurs, GRT Restore selections will not be available for that backup.
If the Hyper-V guest does not have .VHDX disk(s) or the Backup Exec server is Windows 2008 R2, the error will not occur.
Failed to mount one or more virtual disk images
A hotfix is now available for this issue in the current version(s) of the product(s) mentioned in this article. Refer to the Hotfix link under Related Documents at the end of this article to obtain the hotfix needed to resolve the issue.
Backup Exec 2012 Rev 1798 Service Pack 4 (TECH212772).
Backup Exec 2012 running on a Windows 2008 (not R2) server
Windows 2012 Hyper-V guest with .VHDX disk(s) configured