Installing Web Screens crashes IIS

SOLVED

After failed install at client, test as follows.

New VM with Windows Server 2019 and SQL 2019.

Configure IIS.

Install Sage 300 with Web Screens. It stops Windows Process Automation Service (WAS) and therefore IIS stops.

Did restore and installed Sage 300 without Web Screens. All ok. Also services running.

Modified and added Web Screens, crashes WAS and IIS.

What am I missing?