Internet Explorer "Connecting to site 1.0.0.0" and Page Not Found Error

A really weird error happened on one of my older computers, running Windows XP SP2. I successfully established a Wireless connection with an external USB adapter. I opened Internet Explorer and typed a valid address, just to see this strange message in status bar of the browser:

Connecting to site 1.0.0.0...

followed by the infamous Page Not Found screen.

I double-checked Internet Settings Connection tab in IE, I flushed the DNS caché using ipconfig /flushdns command, I disabled IPv6 protocol for the network connections, I reset the adapters....and nothing helped.

Then, searching on Google, I found a deus-ex-machina workaround the solution:

• Download WinSock XP Fix 1.2 (alias WinSockFix) from here
• Unzip and run the tool
• Reboot the PC

It worked for me, at least. This tool resets the WinSock (low-level network layer of Windows) configuration to default Windows settings. I suspect that a "rogue" application ruined those settings and was uninstalled without reverting to the original ones, provoking that IE couldn't make a valid DNS lookup.