Avast can't connect to the server to update, and won't allow any internet access, except for my home page, which is a university website.
My PC is XP Media Center Edition, Service Pack 3. Windows Firewall
I previously had a trial version of Norton, removed that through Add/Remove first, and then tried the Norton Removal Tool, which also didn't work. I added the relevant Avast files to the exceptions list in the Firewall, no help.
I can only access the internet when i stop On-Access protection, which renders the product totally useless.
The only other AV-ish program I run is Spybot S&D.
I'm not totally tech-illiterate, but I'm far from an expert.