Microsoft Windows Servers 2008 is an update release of the Microsoft Microsoft Windows Servers 2008 operating system. Built on Microsoft Windows Server 2003 with Service Pack 1 (SP1), R2 takes advantage of the stability and security of a proven code base while extending connectivity and control into new areas. There are several new product features included in Microsoft Windows Server 2008, including the following. Microsoft Windows Server 2003. Microsoft Windows Servers 2008.