Brush appering in game but not hammer

[Jason Lipscomb]

I am having an issue. When I'm in hammer I don't see this brush. I even tried deleting the brushes near it and replaced them and it still is doing this in game. If you try to walk on it you go through it. Anyone know what's going on?

 

[LemurHugger]

It looks like something in the skybox, is there anything in your 3D skybox?

 

[nesman]

Please use actual screenshots. windows key + shift + s saves one to your clipboard.