If your Windows XP IIS (Internet Information Services) Web server uses FrontPage 2000 or 2003 Server Extensions, or SharePoint Team Services, you may be unable to connect to your Web site after installing Windows XP SP2.
This issue is likely because the Windows Firewall is enabled by default, and it blocks port 80 (the default), or any other port you might have configured.
To fix this problem:
1. Start / Run / ncpa.cpl / OK.
2. Right-click the network connection for your Web server and press Properties.
3. Select the Advanced tab.
4. Press the Settings button.
5. Select the Advanced tab.
6. Select your network connection and press the first Settings button.
7. If IIS is configured for port 80, check the Web Server (HTTP) box. The Service Settings dialog should contain the correct name or IP address. Press OK and OK.
8. If IIS is configured to use port nn, press Add. In the Service Settings, type the port nn and press OK and OK.
9. Press OK.