Hello,
From the hardware compatibility list given below check if the device is tested. if it is tested then install latest Veritas drivers and verify results
(title) Backup Exec 9.x for Windows Servers Standalone Drives Hardware Compatibility List (HCL)
http://support.veritas.com/docs/271382
(title) Backup Exec 9.x for Windows Servers Robotic Library Hardware Compatibility List (HCL) (includes tested drives)
http://support.veritas.com/docs/271383
(title) VERITAS Backup Exec (tm) 9.1 - Device Driver Installer (20050115) - Includes Tape Driver Release (20041231) and Robotic Library Release (45) (Intel Only)
http://support.veritas.com/docs/273853
Thanks,
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