The subject behavior can occur if a buggy LSP (Layered Service Provider ), a mechanism that can extend the Winsock network socket facility for applications, is installed on your computer, or if the %SystemRoot%\INF\Netfw.inf is not updated.

To workaround this behavior:

1. Open a CMD.EXE window.

2. Type netsh winsock reset and press Enter.

3. Shutdown and restart Windows XP.

NOTE: The netsh command in Windows XP SP2 can rebuild a corrupted Winsock registry key. I used this functionality in tip 9121 » When you attempt to open the Windows Firewall on Windows XP SP2, you receive Error 10047? If you have an application, like an anti-virus, firewall, or proxy that uses a custom LSP, you will have to re-install the application, because the netsh winsock reset command deletes all custom LSPs.

If the problem behavior persists:

1. Open Windows Explorer.

2. Make sure that your Folder Options are set to Show hidden files and folders:

            A) Use the Tools menu to press Folder Options.

            B) Select the View tab.

            C) Check the Show hidden files and folders box.

            D) Press Apply and OK.

3. Navigate to the %SystemRoot%\INF folder, where %SystemRoot% is the folder that Windows is installed in.

4. Right-click the Netfw.inf file (%SystemRoot%\INF\Netfw.inf) and press Install.

NOTE: To turn on or turn off the Windows Firewall:

1. Start / Run / firewall.cpl / OK.

2. Select the General tab.

3. Press On (recommended) or Off (not recommended) and then press OK.