Microsoft Mainstream support for GP

Microsoft Business Solutions Great Plains 8.0
Support for Microsoft Business Solutions Great Plains 8.0 Ends October 13, 2009

Microsoft Dynamics GP 9.0
Support for Microsoft Dynamics GP 9.0 End 1/11/2011
http://support.microsoft.com/lifecycle/?LN=en-us&p1=10479&x=9&y=8

Microsoft Dynamics GP 10.0
Support for Dynamics GP 10.0 End 10/10/2012 – Extended Support End at 10/10/2017
http://support.microsoft.com/lifecycle/?p1=12629

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Microsoft Mainstream support for GP