As documented on the
MBSA 1.2.1 homepage, after October 9, 2007, the MSSecure.XML file used by MBSA 1.2.1 will no longer be updated. After this date, no new security updates will be added to the MSSecure.XML file used by MBSA 1.2.1 and no new versions of the Enterprise Scan Tool will be released.
The above notice only applies to the MBSA 1.2.1 and stand-alone EST tools.
This does not affect the Security Update Inventory Tool (SUIT) or Extended Security Update Inventory Tool (EST) for SMS 2.0 and SMS 2003. These legacy scan tools will continue to function and receive updated catalogs through the
end of the extended support lifecycle of SMS 2.0.