[Kin]

Everytime im try to launch Gmod,he gives me this error:
"Invalid or corrupt background texture materials/console/background01-widescreen.vtf"

[Greatie]

You're missing your background wallpaper (I suggest re-installing GMod to get it back). If you we're messing around with any wallpapers or backgrounds, this might be the problem

[Chaoss86]

I get this error all the time as well, If you have tried reinstalling with no success sadly there is not fix (I've tried reinstalling at least 6 times). It means Garry's Mod is not compatible with your computer/hardware.

[Ideal-Hosting]

Chaoss86 posted:

I get this error all the time as well, If you have tried reinstalling with no success sadly there is not fix (I've tried reinstalling at least 6 times). It means Garry's Mod is not compatible with your computer/hardware.

What? Because a file can not be found, Garry's Mod is not compatible?
Try extracting the file from the gcf manually.

GCFScape - A program to unpack .gcf (Game Cache Files). You can find a small tutorial here.