Game Crashing when launching from intro screen

I’m Playing on PC.
To fix so far I’ve done to reinstalls of the game, as well as verifying the integrity of the game files. Neither of these has worked. It worked yesterday morning on my PC, and yesterday evening on a friend’s computer.
I wasn’t hosting. Either playing on my own account or joining a friend’s game.
Haven’t been able to play my own since last night.
Specifications are AMD FX™ 4100 Quad Core Processor 3.6 GHz

If it’s crashing on the Performing Online Login screen, stop it from syncing with the steam cloud. It’s a corrupt save file.
You may need to uninstall, reinstall, uncheck steam cloud, delete the save folder from userdir/appdata, run integrity check, then launch it.