I got it working again. It's 14.5.5871 b.t.w. This setup does not upgrade these mentioned previous settings.
So, I had to map the IP <-> service again and the SSL certificate and the license, as written before. Esp. the IP settings.
Regarding stopping the service.
I have SM already for many years, and I never had to stop the service first. The setup stopped it automatically and then the upgrade took place. But it may be that IIS, indeed did 'lock' some settings.
There is no error log, yes, there is at smartermail\logs but it does not contain serious issues neither does eventvwr.exe
Thanks.
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