There's a strange issue where my game won't start anymore. I've tried disabling the online save games to see if a network connection might have been the issue. But the error (which is none) remained.

The only thing that happens is that I can choose between workshop and the game. If I press workshop, I just get a white screen with no options.

If I choose the game it gives a load screen with a red exclamation mark. It looks like it's about to start, but then it quits.

What can I try to make it run?