That's just weird. Have you tried re-installing it? I don't think it's an OS issue--I use it on Linux, XP, and 98SE.
I use the home version of XP...might be some ad aware or spybot settings.
Windows IDs excite.com as an "unsafe zone" and a couple spyware programs ID their cookies as spyware....
sometimes its fine, but about 2/3 of the time excite just locks up....