Have you... as the warnings suggested... reviewed the Windows "Microsoft 
Application event log" on the client server?  Did you see any useful messages?

Here is some troubleshooting help directly from IBM: 
http://publib.boulder.ibm.com/tividd/td/TSMM/SC32-9103-01/en_US/HTML/cli_vss.html#VSS_symptom_list

Mike

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
SOV
Sent: Wednesday, April 03, 2013 10:42 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Backup failing due to snap shot issue

Hi Zoltan
Thanks for your reply. Its a windows server 2003,standard edition,SP2 Let me 
know if any other info required.

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