Hi,
An upgrade from 9.0-9.1 is a free upgrade!
You may download 9.1 from the following link:
VERITAS Backup Exec (tm) 9.1 for Windows Servers revision 4691.1 (Single .ZIP download)
http://support.veritas.com/docs/264658
Please check whether the device is tested in HCL:
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
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