Hello,
Check in the Widows Event Viewer , System Logs, if you got any errors from the Tape drive or the SCSI Controller(Event ID's 5,7,9,11). This indicates hardware failure.
You may also refer to the technote given below
(title) How to troubleshoot issues with a Robotic Library or Tape Drive in Backup Exec 9.x and 10.0
http://support.veritas.com/docs/255501
Also ensure that the firmware used is up-to-date.
Also Ensure that the device is online.
This is a device related issue.
Thanks
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