Hi,
Are you using AOFO during backup?
Are you backing up exchange database?
Are there any errors in event log?
Check if VSS (Volume shadow copy service) is running.
Test backup with NT Backup.
Additional Information :
For information on the recent VERITAS Backup Exec security vulnerabilities, including links to the downloads for the necessary hotfixes, please refer to the following document:
Patch summary for Security Advisories VX05-001, VX05-002, VX05-003, VX05-005, VX05-006, VX05-007
http://seer.support.veritas.com/docs/277429.htm
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