The Backup Exec Version 10.1 build 5629 is the latest version of Backup Exec.
* Start the installation over the existing installation. You need not uninstal the earlier version.
Symantec Backup Exec (tm) 10d rev. 5629 for Windows Servers Installation Files
http://support.veritas.com/docs/279332
You only need to reinstall the remote agents. Here is the link:
How to perform a local installation of the Backup Exec Remote Agent for Windows Servers or the Advanced Open File Option
http://support.veritas.com/docs/258982
Hope this helps!