Hello,
Please check whether the autoloader is "tested" in the list below, if yes then please install latest veritas drivers from the link below:
Symantec Backup Exec for Windows Servers (tm) 9.x (9.0, 9.1) Hardware Compatibility List. Includes HCL information for supported drives, libraries, virtual tape devices, fibre-channel HBAs, switches, routers/bridges, and iSCSI components. For printing purposes, the latest version of Acrobat is recommended.
http://support.veritas.com/docs/282347
VERITAS Backup Exec (tm) 9.1 - Device Driver Installer (20050115) - Includes Tape Driver Release (20041231) and Robotic Library Release (45) (Intel Only) http://seer.support.veritas.com/docs/273853.htm
If not tested then please install latest manufacturers and then verify the result.
thanks,
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