Windows Desktop Life-Cycle Guidelines

Responding to requests from customers and partners for a clear-cut Windows operating system life cycle, Microsoft is providing public guidelines that it will make licenses for desktop versions of Windows available for five years and assisted support available for four years. These guidelines allow customers to make more informed operating system deployment decisions.

In an update to the Windows product information Web site in Feb. 2001, Microsoft identified three life-cycle phases: mainstream, which applies to the first three years of general availability; extended, which applies to the fourth year of more limited availability; and non-supported, for the fifth year. (See the table “Windows Desktop Life Cycle Phases“.)

The desktop life cycle applies to all non-server and non-embedded operating systems currently in production at Microsoft, from the last version of DOS (6.22) all the way up to Windows 2000. As most corporate customers are still using either Windows 98 or Windows NT 4, Microsoft has put these popular versions at the same point in the lifecycle, even though they were released at different times: both start the extended phase in June 2002, and the non-supported phase in June 2003. (See the table “Windows Desktop Life Cycle Dates“.) Similarly, MS-DOS and Windows 3.1 enter the non-supported phase in Dec. 2001, even though both were released at different times. Windows XP, currently scheduled to ship in 2001, would enter the extended phase in 2004 and the non-supported phase in 2005.