After my last post I used the search function once more in regedit to check if it is present on an unexpected location (hardly probable I thought) and lo and behold! It is there, in aforementioned location. I removed it. Rebooted. Problem gone! Rebooted again. Problem still gone!
For the time being at least: StopServiceRestart may not be present, it apparently can one day appear out of the blue. :o
What was the location you found it at before you deleted it?
In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce allright (the only “aforementioned location” but I understand you want to be certain because of how I said it). Where it was not before as visible in my screenshot. I did not remove it before, it was not there. No other alterations (installs or deinstalls, or updates) have been made. In between I only worked on spreadsheets and via browsers.
I’m pleased your issues is resolved, thanks for your feedback. :-TU
Shane.