Here is my response to your suggestions:
I am running Windows 10 (as it says in my sig!)
I deleted the prefs folder and after rebooting CB9 I actually got VST Connect Pro to work, but only once!!
When I tried a new session, an hour later and after closing down my computer, I got the “VST Connect not installed correctly” message again.
So I trashed my prefs AGAIN, thus loosing all the changes I had made to the appearance of CB9, and again, VST Connect Pro worked…sort of!! Lots of break ups, crackles and such but, hey it was a step forward!!
Came to try another session today and, AGAIN, I had the “VST Connect not installed correctly” message, so AGAIN I trashed my pref folder, and AGAIN I lost all the changes I had made to CB 9 , but this time the performer couldn’t hear the track I wanted him to play to at all??? He could hear my talk back and I could hear his talk back and drums, but that was it!!! I had used (to the best of my knowledge) the same settings that I had to trash, but it was no good.
So on my OP I said that the VST Connect programe was a waste of money and, since your email, I have seen nothing that persuades me otherwise!!
I don’t know how it works in Germany but I’m pretty sure that, if you have to trash prefs EVERTIME you use some software, then that software is NOT ready for public release!!!
Another of your points regarding wether or not the VST Connect PRO is installed, in the plug in manager it shows VST Connect PRO, but in Plug in information (programe plug ins) it says VST Connect Pro???
It also shows that v 220.127.116.11 is being used but it ONLY shows VST Connect Pro checked as active?
So in summary, you ticked me off for double posting, and yet have NOT offered anything like a solution, so I feel that I am perfectly entitled to give you and Steinberg a ticking off!!
I will await a response, but I wont be holding my breath, and I will be warning off any potential purchasers of VST Connect Pro because, as I said in my OP, it is NOT working!!
And if there is not a response by Monday afternoon I will re-post this entire post in the Cubase 9 forum to see if that promotes a reaction!!