Virtual Machines backup through Windows Backup fail on a Windows 2012 Server

configured as a Hyper-V host.

Event viewer Application log has the following error:
 
Event ID 517: "The backup operation that started has failed with 
following error code '0x80070020' (The process cannot access the 
file because it is being used by another process.). Please review 
the event details for a solution, and then rerun the backup operation 
once the issue is resolved." 

Unknown.

Symantec is aware of this issue and will update this document when a solution becomes available. It is not necessary to log a support case on this issue. Please subscribe to this article to be notified of any updates.

Applies To

Windows 2012 Server Hyper -V host.

SEP 12.1 RU3