I just bought L4D2 and I noticed when I started up that I do not have any of the skyboxes. I’ve tried reinstalling and they still haven’t appeared.
Here is a shot of whats going on (ignore the prop less roof I don’t know why it’s like that)
Looks like you’ve got some missing props on the roof.
that’s NO GOOD
I think he wants help with his skybox. Have you tried deleting your materials folder and redownloading it?
I also have missing roof props…
Tried that and it didn’t work 
Validated cache integrity?
The missing props I believe is because of a low graphics setting, shader detail maybe. I saw a thread about it in the steamforums a while ago. Can’t help with the skybox, sorry.
I turned the settings up and the roof props appeared ^_^, but the skybox is still not working
Can you post some other screenies of the missing skyboxes? Maybe The Parish?
here’s some more screens
I’m not convinced that you have a problem. I think that’s how it’s supposed to be. if your skyboxes were actually missing, you would see the purple checkers, and looking at some screenies (I can’t check ingame atm) yours look pretty normal.
To me it just looks like the fog settings are way up, obscuring the skybox.
Try reinstalling the game maybe that might help? Also try to verify the left 4 dead 2 game cache
I think Shrike is right. L4D2 doesn’t have much of a skybox, just lot’s of heavy fog. I think it’s to help illuminate zombies in the dark environment… not sure.
Here’s a video to see a comparison of what it looks like when the fog is on and off and what the skybox sorta looks like underneath: https://www.xfire.com/video/1aa3e2/
Behind the fog it’s really just a light blue sky that fades into a black ring along the horizon.
Haha my monitor is also 1680x1050 but I get way better FPS even when recording.
My computer didn’t work as well as it should and Xfire recording sucks. I got a new 1920x1080 monitor with my new computer and can get a solid 100+fps with full settings now.
Most ‘extra shiny’ graphics are tied to shader detail and only appear at high shader detail(such as cubemaps, or Hard Rain). 
But there doesn’t seem to be anything wrong with the screenshots you have provided, bar the missing roof props. :fffuuu:
Ehm, I have all settings to max (bar AA) and I can’t see those props on the roof either. Hell, I can’t even see the shadows… Quite annoying when you’re trying to run from a tank and you get stuck behind invisible props.
Turn AA up.