Cannot open new apps
Recently upgraded from 10.13 to 10.15 (Catalina).
However it will not let me open any newly installed apps. All they do is crash.
Older apps that ported over when I upgraded do open, it's the apps that are freshly installed that do not open.
The installation of these newly installed apps seems to all be OK, other than they do not open.
I did install TechTool Pro 12 to diagnose the issue, but ironically since it's newly installed it also will not open. How do I troubleshoot what is causing these newly installed apps not to work?
Mac mini 2018 or later