I had a weird problem to fix today with my son’s Vista PC. He installed COD 4 and was able to play single player, but when he tried multiplayer it would start to load but then kick him back to the desktop with a Windows crash error. I updated the game to the latest version (1.7) but multiplayer still would not work. So off to Plan B again: Google for help. I found a solution that worked here. Someone listed having the same problem and found the solution was to have a microphone plugged in. Very strange solution – I have been playing PC games for 20 years and have never seen a situation where a microphone was required to play. I am sure the manual or readme file spells this out somewhere, but it seems like a dumb requirement. Or, if you are going to have this requirement, could the game makers be nice enough to add some code to the program to check for a microphone before starting game and actually tell you that the game will not start until you plug in a microphone?