I have Avast Home Version installed on the computer…

It is version 4, and the build is 4.1.357…

I’m using Windows XP Professionel…

I don’t have a Firewall, but I have a router, and the other users on the network can update their computer…

I don’t have any other anti-virus installed…

Yes, but after I reinstalled it, it can’t update, I have also tryed to update manually, but even that wouldn’t work…

Yes, I get some error messages…

If you ask for my log, I will send it,. but I don’t know which of them, you need to see…