Getting Exception in the backup job

Hi, 

I have a Windows Server 2008 R2 where I have installed Backup Exec 2010 R3 SP3, I am backing up two virtual machines, hosted in Hyper-V 2008.

One Virtual machine is Windows 2012 Server standard and the other is windows 2008 R2

The exception I get is "Unable to collect necessary metadata to perform GRT level restore"

Any idea on why this has occured and how to solve this would be much helpful...

Thanks,

Ram