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?