"Could not load library client" upon startup

Hi.
I just updated Gmod and when I tried to start up my game, it gave me with an engine error saying it “Could not load library client.” I uninstalled all things from my addons folder. There’s this folder called “Garry’s Mod BETA” in the addons folder and it has pretty much what GMod beta had, just no addons folder. It was last modified on August 18th though so Idk if it’s a critical file for GMod or not. Any help?

I had that problem until I renamed garrysmod to garrysmodold, and ran the game so it made a new folder, from there install addons and stuff.