Windows Vista Beta 1
Release Date: July 27th, 2005
Build: 5112
Notes: First Official Beta of the next Windows operating system originally code-named "Longhorn".

Windows Vista September 2005 CTP
Release Date: September 13th, 2005
Build: 5219
Notes: Released at PDC 2005.

Windows Vista October 2005 CTP
Release Date: October 17th, 2005
Build: 5231
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Windows Vista November 2005 CTP
Release Date: Cancelled
TAP Members received Build 5259 - but has reported to be quite unstable.
Microsoft announced it plans to back away from scheduled monthly CTP releases.

Windows Vista December 2005 CTP
Release Data: December 16th, 2005
Build: 5270

Windows Vista February 2006 CTP
Release Date: February 22nd, 2006
Build: 5308
Notes: Targeted for the Business / Enterprise Environment. First Milestone for Windows Vista in 2006.
Released different SKU's for this CTP: Ultimate, Home Premium, Home Basic, and Business.

Windows Vista March Interim Build
Release Date: March 24th, 2006
Build: 5342
Notes: Released out of schedule and is not a CTP.
Interim Build showcases bug fixes made from bugs reported from Build 5308.

Windows Vista April Interim Build (Current Build)
Release Date: April 22nd
Build: 5365
Notes: Released out of schedule and is not a CTP.
This Interim Build showcases several major improvements to UAC, as well as UI refinement as we get closer to Beta 2.

Windows Vista Beta 2 Second Quater CTP
Release Date: Expected sometime between April and June
Targeted for a much broader general consumer release with a Customer Preview Program.
Build: TBA
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