Martin that helped locate/workaround the problem
The problem seems to be the file vstscanner.exe
Now I have removed that from the components folder (only that file).
And Cubase now starts up nicely. I can make music.
So I put back my own 3rd party VST(2) plugins, and went to the vst plugin manager and add my plugins folders.
When I press rescan in the bottom, Cubase complaints about “vstscanner for vst3 plug-ins not found! VST3 plug-ins are disabled. Check your installation!”
BUT it does scan and add my vst2 plugins and they are now all working without problems.
I don’t know if any native Cubase VST3’s are not working because of this, or if I’m missing out on anything (?)
Just tried a few, and they seem to load fine.