<P> Microsoft announced the intention to ship . NET Framework 4 on 29 September 2008 . The Public Beta was released on 20 May 2009 . </P> <P> On 28 July 2009, a second release of the . NET Framework 4 beta was made available with experimental software transactional memory support . This functionality is not available in the final version of the framework . </P> <P> On 19 October 2009, Microsoft released Beta 2 of the . NET Framework 4 . At the same time, Microsoft announced the expected launch date for . NET Framework 4 as 22 March 2010 . This launch date was subsequently delayed to 12 April 2010 . </P> <P> On 10 February 2010, a release candidate was published: Version: RC . </P>

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