No Browsers working for hubby

Hi, everyone - I am new but I do get your news via RSS. Hubby and I both have Athlon 3000 computers, 512mb ram, and access the internet with a cable modem via a router (wired). Yesterday we had a power outage and when our power was restored, hubby could no longer access the internet on any browser. He has Internet Explorer, Crazy Browser, Netscape and Firefox - get "page cannot be found" on all. We both run Win98SE, fully updated. He has tried various fixes including winsock fix. It is like port 80 is blocked now on his computer. He can send and receive email, MSN Messenger works, his P2P (WinMX) works, he can ping and traceroute. He just can't get any of his browsers to work. Is it possible the power failure did something? Any ideas out there? Thanks in advance - yes I did check for something similar on a search here but those things mentioned were/are not the problem.