Already looked at that link but did not solve it.
How does your SQL connection string look like? I tried with this: Server=<db server>;Database=<db>;TrustServerCertificate=True;
Have tried removing the appsettings file after failure too, to make sure correct parameters were used.
Only thing I have in event manager is: Product: PowerShell Universal -- Error 1923. Service 'PowerShell Universal' (PowerShellUniversal) could not be installed. Verify that you have sufficient privileges to install system services.
I would suggest doing an uninstall and then reinstall. During the reinstall, try to uncheck the service “Start service” check box. After install, try to set the service account manually in services.msc and see if the service starts up.
Seems to be a problem related to the RunAS function. Was able to install PSU without providing any credentials, but when I then insert my RunAS credentials afterwards in the Windows Service I get following:
One other thing I would suggest would be to check the permissions on the C:\ProgramData\PowerShellUniversal and C:\ProgramData\UniversalAutomation folders. Verify that the service account has access to these directories.