Mainstream support will be retired on Dec. 31, 2003. Mainstream support includes all the support options and programs that you receive today, such as no-charge incident support, paid incident support, support charged on an hourly basis, support for warranty claims and hotfix support.
Extended support will be retired Dec. 31, 2005. Extended support may include support charged on an hourly basis and hotfix support. In order to receive hotfix support, an extended hotfix support contract must be purchased within the first 90 days following the end of the mainstream support phase. Microsoft will not accept requests for warranty support, design changes or new features during the extended phase.
To learn more about Microsoft's product lifecycles, click here. There's also a lifecycle FAQ for Exchange. As an aside, if you are curious about other products, or if you just want to know where I got these dates from, click here.
Editor's Note: See also SearchWin2000.com's exclusive news article, Microsoft: End is near for Exchange 5.5.
This was first published in November 2002