you could try "winsockfix" or WinSock XP Fix as it is sometimes called. Google for it and give it a try. Malware will modify network settings and then when the malware is removed, the internet connection is lost. Just a thought.
I was cleaning a friend's old system that had several spyware/etc and even a couple of viruses. I used removal tools which seemed to work fine for the viruses. I replaced the outdated Norton Antivirus with AVG(fe). I used SBS&D and AdAware for the rest. The system seemed to be stable again (as opposed to constant crashing/freezing/rebooting). I ran full scans with all three again and everthing seemed clean.
Now however, I cannot connect to the internet. This system was originally set up for dial up, but I also tried using broadband with the same results. At first I thought I might be having problems with my provider, but after running some diagnostic test, it showed that the connection was alive, both in dial up and broadband. With the connection established, they said that it had to be a firewall problem and game me the boot.
So I check the OS, its pre SP2 so it doesn't have Security Center, and I checked the Windows Firewall settings under Connection Management and it showed it as being off. I have not installed any firewall programs, and I doubt it could be my router. Just in case, I tested my router by connecting a couple of computers that were not originally in my network, which worked fine. Also, thinking that it might have been something caused during the process, I tried using System Restore, only to find that all points I had made in between were corrupted.
So now I'm at a loss as to what might be causing this problem. Any thoughts would be greatly appreciated.
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