[Solved] Game Crashing

[Robbtja]

Snowredwolf:
Due to the new Gmod update, we've seen people encounter crashing issues when pressing f1 and joining the server if you encounter these issues you can set your Gmod to development branch for now. 
To do this, you right-click on Gmod in your steam library, press settings, choose betas, then choose Development branch.
After doing this your game will update, if you in the future get a message with your Gmod running another version than the server, then go back to the default branch the same way as you went to the development branch.

This is not a guaranteed fix, however, it has fixed the issue for a few people so far.