In 2002 Microsoft standardized the termination dates for its product support lifecycles. End dates fell at the end of each calendar quarter, which meant March 31, June 30 and September 30, and December 31. As you know, the company also standardized its monthly security update release schedule, which falls on the second Tuesday of each month.
The two schedules clashed and occasionally left companies in the lurch because sometimes security updates are released only days after a product's support lifecycle ends. This month is a prime example. Support for Exchange 5.5 ended on December 31, 2005. However, a critical vulnerability was discovered in Exchange 5.x and Exchange 2000 (the same vulnerability affects Outlook 2000, Outlook 2002, and Outlook 2003) and as such a security update was published on January 9, 2006 -- nine days after support for Exchange 5.5 would have ended.
Microsoft announced that beginning this month, support lifecycles will be synchronized with the company's regularly scheduled security patch release dates. This means that instead of support lifecycles ending on December 31, 2005, for example, lifecycle support will instead end on the second Tuesday of January 2006.
"We changed the end of support dates to map to the monthly security update release cycle so our customers can take advantage of the latest security updates," says Ines Vargas, group manager for Microsoft Support Lifecycle Program. "By eliminating that ten to fifteen day gap, we're making sure that our dates make sense to our customers – that they're even more consistent and predictable."
The new support lifecycle end date changes will affect all Microsoft products and the company will make changes to those published dates during the first quarter of 2006. Microsoft typically provides support for its products for five years. After five years the company provides paid extended support for an additional five years.