Cancelled versions of windows

• April 1985 Windows 1.0 Beta was scrapped, but later became the framework of the first version of Windows.
• 1996 February 29– Cairo (a "true object-oriented OS") planned after Windows NT 4.0 and had the same primary and secondary version numbers.
• 1996 May 2 – Windows Nashville (Windows 96)
• 1999 December 27– Windows Neptune, the first planned version of Microsoft Windows NT to have a consumer edition variant, based on the Windows 2000 codebase. A version was sent out to testers but was never released.
• 2000 January 13– Windows Odyssey, a version intended to be an update to the Microsoft Windows NT 5.x codebase. The teams working on Neptune and Odyssey combined to work on the Whistler project,later released as Windows XP.
• 2005 February 28 – Windows Longhorn cancelled and became Windows Vista in Fall 2006.
• 2009 October 26 – Windows 7 Workstation editions cancelled

Source : Wikipedia.org