This is a 100% fix for the map differs problem. IF you still have the issue after doing all of these, you 100% did not do all these correctly. 1. Make sure your game is closed.  2. Delete the following folders in Garry's Mod. D:\steamapps\steamapps\common\GarrysMod\garrysmod\cache D:\steamapps\steamapps\common\GarrysMod\garrysmod\downloads Find the map in D:\steamapps\steamapps\common\GarrysMod\garrysmod\maps and delete that (it might not be there but if it is dele