The free program, which is slated to be in final form later this year, lets users of the Windows XP, Windows 2000, and Windows Server 2003 operating systems download all updates automatically or manually choose which patches to get.
In a February speech at the RSA Conference 2005, Microsoft Chairman Bill Gates hadthat a beta version of the program would launch this month.
In its current form, Microsoft Update will capture updates to the SQL Server database program and Exchange e-mail and calendaring software, along with Windows and Office enhancements. Microsoft said it hopes to add support for more programs in the future.
Improving patch management has been a key goal for Microsoft, which often finds that computers get hit by security threats long after a security vulnerability has been addressed because the machines are using an unpatched version of the program.
Microsoft said it will continue to offer its separate Windows Update and Office Update utilities for customers who prefer those options.