Microsoft Windows 3.1

Windows 3.1 is a series of obsolete 16-bit operating environments produced by Microsoft for use on personal computers, released on April 6, 1992. The series began with Windows 3.1, which was first sold during April 1992 as a successor to Windows 3.0. Subsequent versions were released between 1992 and 1993, notably Windows 3.11, until the series was superseded by the Windows 9x series starting in 1995.

Official support for Windows 3.1 ended on December 31, 2001. However, OEM licensing for Windows for Workgroups 3.11 on embedded systems continued to be available until November 1, 2008.

Windows 3.1 was designed to have backward compatibility with older Windows platforms. As with Windows 3.0, version 3.1 had File Manager and Program Manager, but unlike all previous versions, Windows 3.1 cannot run in real mode. It included Minesweeper as a replacement for Reversi (though Reversi was still included in some copies).