Windows 2001

Windows 2001 is released in April 22, 2001. Mainstream support end on August 11, 2009. Extended support end on February 15, 2014.

Editions
Windows 2001 Professional

Windows 2001 Plus!

Windows 2001 Server Family

Windows 2001 NET. Server

Windows 2001 Starter

Windows 2001 Home

Windows 2001 Embedded (2003)

Windows 2001 Slim (2003)

Windows 2001 Ultimate

Windows 2001 SE (2014)

Windows 2001 Server

Windows 2001 Server R2 (2002)

Trivia
Windows 2001 has combined with Whistler and XP.

Orginal its September 11, 2009 but was end of mainstream support planned to end on August 11, 2009 for some reason.