Yes as told by John, you need to only install SP2. For more information on this, you can also check the release notes for SP 2:
Release Notes for Backup Exec 9.1 for Windows Servers revision 4691 - Service Pack 2 http://support.veritas.com/docs/275399
Hope this information helps. Do update us in either case. If we do not receive your update within two business days, this post would be marked âassumed answeredâ and would be moved to âanswered questionsâ pool.