09.17.2004 - Programs that connect to IP addresses that are in the loopback address range may not work as you expect in Windows XP SP2 (884020)

This update helps resolve an issue on computers running Windows XP Service Pack 2. Programs that connect to IP addresses in the loopback address range may not work as expected and you may receive an error message indicating you cannot establish a connection. - Download Update for Windows XP - View Additional Information - View Microsoft Knowledge Base Article - 884020 - Visit Microsoft Corporation