FATAL ERROR FIX - Call of Duty 4 : Modern Warfare (COD4)
so what you wanna do first is quit the game and now what you want to do is disconnect your internet by unplugging your wireless router from your plug or removing the Ethernet cable from your PlayStation
after you've done that you want to start the game back up and wait until you get to the multiplayer menu
when you've got to the multiplayer menu you want to plug back in your wireless router or your Ethernet cable and wait until you can sign back into the PlayStation network, this may take a while for your internet reconnect
once you've finally reconnected simply press play online just like normal. if this video helped you in anyway please give it a thumbs up