Hey Hey,

I've got a few questions to get the ball rolling. I'm awake at 4:30am with insomnia, so I'm in no condition to be giving advice, I'll leave that for the early risers a few hours from now. In the mean time, ponder and answer these, they will help us provide you with a more formulated hypothesis (big words. heh)...

1. Changing What kind of things?
2. Do you keep your computer completely update?
3. Someone stole your McAfee? Please elaborate. Do you have AV or not? Is it updated? If not, next time you're online try using TrendMicro's Online Housecall AV. http://housecall.trendmicro.com/
4. Are the two computers networked? i.e. Is there a crossover cable, or two straight-through cables and a hub/switch connecting your computers?
5. Do you keep AdAware up to date? Have you tried using Spybot S&D? http://www.safer-networking.org.

That should be enough to get the ball rolling. Remeber detail is key. The more you give, the more we can provide (as far as a solution/remedy goes). Even something that seems very mundane could be useful, just don't violate you privacy and give out personal information.

Peace,
HT

[Edit]
Just an FYI for f2b. You said
Do you have file and Print Sharing enabled?
If yes then disable this immediatly!
He mentioned using the Windows Firewall, it will have blocked File and Print Sharing... It's one of the quirks of that "wonderful" firewalling software.
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