Hello,
Try recreating the backup job but with a new selection list. Such errors are attributed by corrupted messages, that Backup Exec either skips or throws this error whilst trying to backup.
Also check whether the Backup Exec Service Account has sufficient rights/privileges over the Exchange Resources.
The following document explains which rights are essential for the BESA to protect an Exchange server
http://support.veritas.com/docs/234575
Please inform us about the results.
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