Hello,
You have mentioned in your post that the mail server is running on NT4. Kindly note that the Backup Exec v10.0 does not support NT4 Operating System.
Please refer to the below mentioned SCL:
Backup Exec 10.0 for Windows Servers - Software Compatibility List (SCL)
http://support.veritas.com/docs/264484
Therefore, cannot gurantee the functioning of Backup Exec during the backups.
Regards
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