One day one of my friends called me very early in the morning and was going nuts over his network connectivity. I asked him about the problem and he said that he can not connect to internet and only message he can see in the tray is "Connection has limited or no connectivity". He told me that it was wroking fine night before. So obvious question I asked him was what changed between yesterday night and this morning. And he said that he installed an anti-virus and firewall from a very well know vendor. And immediately bells started ringing.

I was the one who setup his wireless modem and connectivity at first place. And it was using WEP security. So I asked him to delete the wireless profile and recreate and re-enter the security key and other information. That did not resolve the problem. I thought his profile was corrupt. Next thing I checked was the TCP/IP settings and they were correct too. I did not check the cable modem and wireless router because my laptop was connecting fine.

Then I uninstalled the AV and Firewall he had installed last night because that was the only thing he did that was different from the configuration he has prior to the problem. Uninstall did not work. And thats when I started looking around and found the cause of the problem. And this problem is very common to Antivirus, Adware, Spyware removal tools. Sometimes these tools corrupt the registry settings for WinSock or corrupt the files for socket connections. And when you try to uninstall them, they create even bigger problems. And this our well know vendor seemed to have the same problem.

I found this very handy utility WinSock XP Fix which fixes the registry settings and fixes the connectivity problems. I have tried it on couple of machines so far and it seems to work perfectly.