This is an update for Microsoft Library 1.0. MLU 1.0, which resolves the vulnerabilities that cause some third-party software applications to behave unexpectedly after the installation of the Microsoft Works Suite 99, Encarta Encyclopedia 99 (U.S. only), Encarta Virtual Globe 99, and Studio Greetings 99.

This update also addresses a Year 2000 issue that causes some applications that are built with the Microsoft Foundation Classes to improperly handle dates that are later than December 31, 1999. In addition, this update addresses an unrelated April 1, 2001 date-handling issue.