If it’s a problem regarding the map he simply will need to go to his Garry’s mod folder and remove the maps there and reinstall them by either verifying cache or joining the server installing whoever map is requested and his map textures will be fixed however actual Garry’s mod texture problems might be fixed by getting csstextures or making sure he correctly installed them or has them

If it’s a problem regarding the map he simply will need to go to his Garry’s mod folder and remove the maps there and reinstall them by either verifying cache or joining the server installing whoever map is requested and his map textures will be fixed however actual Garry’s mod texture problems might be fixed by getting csstextures or making sure he correctly installed them or has them