Password: qwerty13579. Windows Server 2012 R2, codenamed "Windows Server Blue", is the seventh version of the Windows Server operating system by Microsoft, as part of the Windows NT family of operating systems. It was unveiled on June 3, 2013, at TechEd North America, and released on October 18 of the same year. It is the successor to Windows Server 2012, and is based on the Windows 8.1 codebase.