Microsoft and IBM open source MS-DOS 4.00

Microsoft, in partnership with IBM, has released the source code of MS-DOS 4.00 under the open-source MIT license. This release comes a decade after Microsoft first made the source code for MS-DOS 1.25 and 2.0 available to the public through the Computer History Museum. The decision to release the MS-DOS 4.00 source code was inspired by the discovery of early, unreleased beta binaries by researcher Connor “Starfrost” Hyde. Hyde’s discovery stemmed from a conversation with former Microsoft Chief Technical Officer Ray Ozzie, who unearthed the binaries among floppies sent to him during his tenure at Lotus. Intrigued by the software’s… [Continue Reading]