Texture issue

http://cloud-4.steamusercontent.com/ugc/541889413273235856/5F8F6A02CCB139E2DAE83B994000F28585C4C14E/

Anyone know to to fix those squares I get them on most of my maps

With out knowing what that map is called I couldn’t tell you what textures you need. But generally you should have HL2, HL2 EP2, CSS and Portal 2.

Seems to be the subway from L4D1, if you don’t have that, get it.