Symantec Backup Exec 2010 Windows Agent inside Windows Server 2008 Hyper-V Machine

[playpiano]

Symantec Backup Exec 2010 Server with all available patches installed in Windows Server 2008 R2.
Symantec Backup Exec 2010 Windows Agent + Exchange Server 2007 are installed in a Hyper-V Windows Server 2008 (non R2) Virtual Machine  (and Hyper-V is hosted by Windows Server 2008 R2).

No way to backup what is inside Virtual Machine.

Naturally i try to backup Exchange Server 2007 but the backup stall; i have to restart Symantec and Symantec Backup Agent (error E0008821).

So i try to backup only System Status and Shadow Copy Component: in this case the backup start but at some time stall the same way (error E0008821).

Please, help me!

[teiva-boy]

Have you looked at the plethora of KB articles and even google results for that error code?  It's a place to start!

[playpiano]

Yes, i look for a solution but found nothing, nothing.
And i don't understanda how to resolve it.