I am replying here rather than starting a new topic, because the problem is the "same".
I recently got a little malware on my PC somehow, and since it got in, I can't update avast any more. I assume it's related.
The problem persists even after it's (presumably) gone.
Similar problems though:
FireFox works fine, but IE8 doesn't find internet. My IM programs (MSN, ICQ) have no problems connecting.
The difference here is that I have no firewall, and Windows firewall is deactivated, and this still comes up. I have tried to find settings for something regarding this, but has not been in any luck.
After some more fiddling I realize some programs have no problems connecting to internet, while others do. IE told me "Windows cannot connect to internet", so it must be related to that somehow. Some programs connect direct to internet, and others connect to Windows' internet? Windows XP btw. SP3. managed to update all thing before this.