Hello,
No symantec Software will "FORCE REBOOT" any operating system, you will be prompted to reboot the server, you can QUIT with reboot.
After the REBOOT you need to update all the Remote Agents by re-pushing them. A REBOOT is required before pushing the remote agents.
http://support.veritas.com/docs/274163
How to push install the Backup Exec Remote Agent for Windows Servers in Backup Exec 11d & above
Hope this helps !!!