it's a known problem with all p2p networks.
Whenever I'm stumped, I try to start fresh by running the uninstall program and deleting the old preferences--even deleting the old incomplete folder.

All the upstream connect problems I can think of are irrelevant, since your roommate who has the same setup (including LW version?) can connect fine (unless the telephone/ethernet cable is flaky). If you take whatever cable that plugs into your roommate's machine and plug it into yours, that will certainly tell you if the problem is in your box.

Where? Hmm. If a clean install shows it's not LW, then I'd compare the Java version, memory allocation, and extensions conflict. After that, sounds like Norton needs to take a look.

The easiest would be to closely compare both the setups to see why one works and the other doesn't.

Let us know how it goes--this is bugging me too.