I went to Japan for study abroad and they messed with the proxy address of my computer and now that I'm back in the states I don't know how to change it back and I can't get onto any web pages. I'm connected to the internet and everything, but when i click on mozilla or explorer it says
"Unable to find the proxy server
firefox is configured to use a proxy server that can't be found"

please help! I'm about to throw my computer at a wall like a caveman!