Hello Marcel,
Install the latest Veritas device drivers from the link mentioned below and the create the IDR bootable cd and check the results.
Symantec Backup Exec (tm) 10d (10.1.5629) - Device Driver Installer (20060215) - Includes Tape Driver Release (09) and Robotic Library Release (52) (Intel Only)
http://support.veritas.com/docs/281696
Regards
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