Wont let me open my game on my desktop. It wont open my launcher or anything. What should I do?

Put the summary of the bug you're having here

What I expected to happen was...:
it would open my launcher as usuall and i could play.

What actually happened was...:
it wont let me open my game.

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...