TandbergTape library problem

Dear All,

                  I have a query in our environmen tandberg  tape library LTO-4 is use for back purpose Symantec Back Exec  2012 is use  and install on virtual machine operating system  server 2008 R2 tape library is detected in Back Exec 2012 "tape drive 0001 HP ultrium 4-SCSI Tandberg library is attached to the SAS cable and the virtual machine we use is  vmware. but Slots is not showing on the Back Exec software how  can i resolve this problem.

Thanks in advance

Regards,

Fasih