Can't launch 4.26 after upgrading from Preview 4 to 5

Just upgraded from 4.26 preview 4 to 5 and now I can’t even launch the editor. Get a pop up error PythonSCriptPlugin failed to load

What can I do to fix this?

320429-pythonscriptplugin.jpg

Answer seemed to be I had to completely uninstall UE4.26, and reinstall from scratch. The issue was with the upgrade.

Hi , just curious what you mean by upgrading the preview from 4 to 5 ? Does that mean the shader model?