GMod Crashes on Join 2021
There are multiple reasons that you could be crashing while joining a server. A majority of the time, this is a user based issue and can be solved!
1. Deleting Addons
a. While on the main menu, click on "Addons". Navigate to the wrench at the bottom right and select "disable all". Restart your GMOD client and try reconnecting to the server. Try step b if this does not work.
b. Verifying your Cache
While gmod is not open, right click on it in your steam library, and navigate to properties. Click on "Verify integrity of game files" Let the process complete and relog into the server.
c. Fresh Install
If step a or b did not work, do not fear. 99% of the time, this is a sure fix for these kinds of issues. Right click on GMOD in the steam library and select uninstall. Reinstall and relog!