Q:

Backing up Hyper-V VMs using "wbadmin" failing on Windows Server 2012

I'm trying to backup a single VM using "wbdamin".
I'm using this command-line:
wbadmin start backup -backupTarget:d: -hyperv:VM_Machine_Name -quiet

But the backup have no success. Looking at my Events, I get the following information:
Source: SSP

Event ID: 16387

Level: Error

"Writer Microsoft Hyper-V VSS Writer experienced some error during snapshot creation. More info: ."

=============================

Source: Backup

Event ID: 521

Level: Error

"The backup operation that started at '‎2014‎-‎06‎-‎11T15:38:44.459000000Z' has failed because the Volume Shadow Copy Service operation to create a shadow copy of the volumes being backed up failed with following error code '0x8100010C'. Please review the event details for a solution, and then rerun the backup operation once the issue is resolved."

=============================

Source: VSS 

No Event Errors.

I didn't find any info about "0x8100010C" error code through the web and I'm stuck. Anyone know how to fix this?

A:

I also got the same error code: 0x8100010C yesterday.
Later I found it seemingly happened because I tried to put the backup to the same partition where the VM's VHDX file resided -- looks hyper-v doesn't allow this, but the error code is really so obscure
Hope this helps.

