Graphic Node Out Of Date

Ok, so I have a problem with this message : “Graphic Node Out Of Date : Rebuilding …”. It appears every time I play GMOD on a TF2 map. It disappears after 30 seconds, but after that my game becomes very laggy.

I tried to re-install GMOD but I still have this message.

Can you help me ?

-Thanks-

[editline]10:08PM[/editline]

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