Thanks. I reviewed the upgrade/installation manual prior to my upgrade, though it didn't completely address the issues for a cluster upgrade that I experienced.
I just found a new document... "Release Notes - Additional Operational Notes" that may help me. http://ftp.support.veritas.com/pub/support/products/NetBackup_Enterprise_Server/278130.pdf
Veritas / Symantec left out any automatic process in their installation code to perform a full NBU upgrade in a cluster configuration on a Windows VSFW and NBU 5 > 6 environment.
It appears that after installing the NBU software, the virtual server has to be added using the syntax:
nbemmcmd -addhost -machinename virtual_name -machinetype
app_cluster
where virtual_name is the virtual name of the application.
Then the command here has to be executed.
nbemmcmd -updatehost -add_server_to_app_cluster -machinename
node_name -machinetype media -clustername virtual_name
-netbackupversion 6.0 -masterserver master_name
Repeat the above step for each node on which the application can run.
I'll test this next week and see if it resolves the problem.