Hello,
Please refer the following technote. This maybe helpful. however if this is not the case, do revert.
Title:
Remote Agent service terminates While Backing Up the System State on a Domain Controller.
http://support.veritas.com/docs/242153
As for error 'unable to attach to one of the drives' , we will troubleshoot it after troubleshooting the above mentioned error.
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
NOTE : If we do not receive your reply within two business days, this post would be marked assumed answered and would be moved to answered questions pool.