Hello,
Plese refer the following the tech notes
http://support.veritas.com/docs/265167
VERITAS Backup Exec (tm) 10.0 for Windows Servers General Information
http://support.veritas.com/docs/264482
Release Notes for VERITAS Backup Exec (tm) 10.0 for Windows Servers revision 5484
http://support.veritas.com/docs/275293
Release Notes for VERITAS Backup Exec (tm) 10.0 Service Pack 1 (SP1) for Windows Servers revision 5484
http://support.veritas.com/docs/265163
Upgrading from Backup Exec 7.x for Windows NT to Backup Exec 10.0 for Windows Servers
Also recommend you to backup the catalogs,and data folder before the upgrade
Regards,
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