Backup Exec media server will connect an unlimited number of individual "stand alone" backup drives, physical or virtual, optical, or one single backup drive within one physical or virtual autoloader, library, robotic library or robotic media changer.
kindly refer the following HCL and check for the autoloader and its compatibility with Backup Exec software.
You can cross-check the HCL from the link given below:
http://support.veritas.com/dsl/verselect_ddProduct_BEWNT_prod1_NT9.htm
If the device is present in our HCL, kindly refer the following steps.
Kindly download latest device drivers. We recommend you upgrade to initially to 9.1 and then install the following device drivers.
As an additional information, Kindly refer the following technote link.
How to troubleshoot issues with the "" and "Tape Drives" in VERITAS Backup Exec (tm) 9.x for Windows Servers
http://seer.support.veritas.com/docs/255501.htm