If a virtual client exists, when NetVault Backup is upgraded, there will be some files and folders copied to the pit.pre\vmachines folder. If that virtual client is then deleted and NetVault Backup is later upgraded again, the upgrade will fail.
Virtual Client pit.pre\vmachines folders still exist for virtual clients that don’t no longer exist.
NetVault Backup will need to be removed and installed again. Then the NetVault Backup database can be restored from a backup. Delete any folders in the pit.pre\vmachines folder with names of virtual clients that do not exist. Then attempt the upgrade again.
