AOFO Snapshot failures

I am trying to run backups against a server running W2K Exchange Server. I keep getting the error below. I have searched the k-base but can't come up with any relevant ideas. Any thoughts?
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AOFO: Initialization failure on: "\\LINCOLN\Microsoft Information Store\First Storage Group". Advanced Open File Option used: VERITAS Volume Snapshot Provider (VSP).
Snapshot provider error (0xE0008516): Resources specified for snapshot do not have any valid data on them. Check if files were deleted or renamed.

Check the Windows Event Viewer for details.
Network control connection is established between 192.168.5.6:3253 <--> 192.168.5.4:10000
Network data connection is established between 192.168.5.6:3254 <--> 192.168.5.4:5467

Set Information - \\LINCOLN\Microsoft Information Store\First Storage Group
Backup Set Information
Family Name: "Media created 5/5/2005 1:23:32 PM"
Backup of "\\LINCOLN\Microsoft Information Store\First Storage Group "
Backup set #1 on storage media #1
Backup set description: "Backup 00009"
Backup Type: Full - Database & Logs (flush committed logs)
Microsoft Exchange Server Agent: Started




Backup started on 5/5/2005 at 1:23:46 PM.

Backup Set Detail Information



Backup completed on 5/5/2005 at 1:29:58 PM.

Backup Set Summary
Backed up 1 Exchange Server stores
Backed up 3 Exchange Server logs
Processed 4,296,168,080 bytes in 6 minutes and 12 seconds.
Throughput rate: 661 MB/min