Thanks L.J. for your help!
Yesterday I’ve found out some things.
Vitalizer was on an other path then where I looked before all the time.
There’s actually 2 different paths:
The system vst3 folder path is:
/Library/Audio/Plug-Ins/VST3
The path for the user one is
/Users//Library/Audio/Plug-Ins/VST3
I knew it had to be somewhere, but strangely enough I can’t find it with Spotlight
Somehow Spotlight or find in finder hasn’t filed it???
Now I removed Vitalizer and C6 finally works!!! there was a lot of rubbish in my VST’s; (I collected this rubbish in more than 10 or 15 years working with Cubase,) so I had to forcequit C6 a lot of times and re-open again, so that C6 can put the old and not working VST’s in the blacklist (if I understand well)