Windows Server 2008 R2

Windows Server 2008 R2 is the server counterpart of Windows 7, which reached RTM on 22 July 2009 and was released on 22 October of that year, becoming the first server release to ship day-and-date with the client counterpart since Windows 2000 Server. This release drops support for the x86 architecture. It was also the last version of Windows Server to ship with the IA-64 architecture and to receive a Service Pack from Microsoft.

This is the last version of Windows Server to support processors without PAE, SSE2 and NX (Update KB4088875 removes support for processors without SSE2) and include Enterprise Server and Web Server SKUs.

It replaces Windows Server 2008 and was replaced by Windows Server 2012.