Don't try looking for games on LAN. If you want to play in servers, go to Internet Games,
not LAN Games. You probably did that since you most likely play at PC Bangs and that's usually how you would connect to the server. Through LAN. If you want to create a game, create it in Internet Games, if you want people to join and play with you.
*If you want to play with BOTS, then LAN Games it is, although i'm not so sure about this "Class C" error you're getting. Try what Mr. Satan pointed out to you...
Mr. Satan said:
Yeah, or he has mp_lan "0" in his listenserver/server .cfg