Re-install steam and re-download half-life 2 Go back to your SteamApps folder and delete the entire half-life 2 folder. Go to your SteamApps folder and find your half-life 2 folder and copy it to any dir.
well, I assure you, I have found the way and this is no 'bogus' fix, well at least it worked for us! :grinthumb.
I couldnt help but notice how many people have posted about this problem and how many bogus fixes there have been.