Support for Microsoft Software Update Services (SUS) ends on December 6, 2005.
SUS has been replaced by Windows Server Update Service (WSUS). Update content will no longer be available through SUS after December 6, 2006. To receive critical updates for your network, you must upgrade to WSUS.
WSUS also provides additional benefits over SUS. In addition to Server and Client Operating System software updates currently available through SUS, WSUS supports critical updates for Office 2003 applications.