Call of duty 4 in game error

[Biggles_me]

I've been playing for a while with no problems, progressing through nicely, and i've got to the launch facility level, part A, and i've just rapelled into the silo hatch things and then i get the usual load screen, except the game quits, and i get an error message saying the quickfile to do with launchfacility_b is corrupt or unreadable

i really wanna fix it i was enjoying playing! help!

[Keymaker]

Is the disk clean?

Has the hard drive been defraged latly?

The COD4 disk seems to be a real PITA.

If this is a \/\/4r3z then there isn't going to be much help here.

[Biggles_me]

it's not from a disc i downloaded it from steam, and this laptop is only 2 months old and there's not much on it!

[Keymaker]

Ahhh, steam is crap. IMO. It may be their issue.

[Biggles_me]

it's just that the rest of the game has run completely without issue, i haven't seen an error like this before, can i not track down the file and fiddle with it or do these sorts of things not work like that