fgl, is your backup destination a CIFS share or VMDK? If it's CIFS, make you have a clean, fast path from the VDR host to whatever is hosting your destination share. It's possible if you're having transient network problems, VDR may think the destination is partially damaged even though it was a network error that caused it not to be able to read the data. If it's a VMDK, is it a locally attached disk? SAN? NFS?