Way OT: Internet Connection

[Grandpa Kim]

Boy, do I need a super expert!

Three computers in the house and two can get onto the 'net, mine can't. It could yesterday and can't today. I've changed no hardware or drivers, just one day can next day can't.

I've tried everything:
--direct connect to the cable modem. (to be fair, this is my usual solution and has always worked in the past)
--turn everything off then on again.
--cleared history and Cache.
--checked the ethernet card. It's working properly.
--checked device manager; no joy.
--looked in windows help. Okay, you can stop laughing now; sometimes you get lucky.

I'm just about out of ideas.
--should I clear the cookie file?
--is my IP address a problem? If so how can I change it?

My computer
Dell Dimension running Win XP Home
Netscape 7.1
Broadcom 440x 10/100 Integrated Controller

... and lots more info if you need it.

If you are interested in taking a whirl at this problem tell me what you need and I'll dig out the info.

Thanks
Kim