Hello Bryan,
Do you have an extra LEO License for the extra drives? Only the first Drive is supported by default in Veritas. For all the other driver a LEO (library Expansion Option) shoud be bought.
If you already have one then try the following:
1) Check if the device in the HCL as tested or compatible or tested. If mentioned as tested use the latest Veritas drivers. If your device is mentioned as Compatible use OEM drivers. Please go through the following documents:
Backup Exec 10.0 for Windows Servers Standalone Drives Hardware Compatibility List (HCL)
http://seer.support.veritas.com/docs/274347.htm
Backup Exec 10.0 for Windows Servers Robotic Library Hardware Compatibility List (HCL) (includes tested drives) http://seer.support.veritas.com/docs/274348.htm
VERITAS Backup Exec (tm) 10.0 - Device Driver Installer (20050115) - Includes Tape Driver Release (20041231) and Robotic Library Release (45) (Intel Only) http://seer.support.veritas.com/docs/273887.htm
2) Update your drives with the latest Firware
3) Run the Device Configuration Wizard of Backup exec (as suggested by Ken)
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Also go through the following Article:
How to resolve hardware communication/detection issues with Backup Exec
http://seer.support.veritas.com/docs/237047.htm
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Let us know if that helped you.
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