After deploying the robot_update 7.90 to the complete domain, the primary Hub was lost.
The Nimsoft Service Controller task did not start up, the information in the task were not filled in. Even restarting the the hub server did not help.
During our research on the system, we noticed in the C:\Program Files (x86)\Nimsoft\robot directory that 3 files has been renamed most likely due to an incomplete robot update with .7.90
After renaming them back by removing the ".7.90" extension the controller started up.
Files with ".7.90" extension were: