Microsoft Minesweeper is a minesweeper computer game created by Curt Johnson, originally for OS/2, and ported to Microsoft Windows by Robert Donner, both Microsoft employees at the time. First officially released as part of the Microsoft Entertainment Pack 1 in 1990, it was included in the standard install of Windows 3.1 in 1992, replacing Reversi from Windows 3.0. Microsoft Minesweeper has been included without a major change in all subsequent Windows releases until Windows Vista, at which time an updated version by Oberon Media replaced it. In Windows 8 and later the game is not included, but Microsoft Studios published an updated version of it, developed by Arkadium, on Windows Store.