From BetaArchive Wiki
Logo of MS-DOS

MS-DOS (Microsoft Disk Operating System) is an operating system for x86 based personal computers. It was based on 86-DOS (Quick and Dirty Operating System), also known as 86-DOS, which was made by Tim Paterson and purchased by Microsoft. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for personal computers during the 1980s and 1990s. It was preceded by M-DOS (also called MIDAS), designed and copyrighted by Microsoft in 1979. MS-DOS was written for the Intel 8086 family of microprocessors, particularly the IBM PC and compatibles. An MSX port was also made, called MSX-DOS.

It was gradually replaced on consumer desktop computers by operating systems offering a graphical user interface (GUI), in particular by various generations of the Microsoft Windows operating system. It is still used by a tiny market niche where legacy DOS applications are still required, but no modern version is available.

Microsoft and IBM both had their own versions of MS-DOS. There are not many differences between the two versions before the split up, when IBM started developing PC-DOS independently of Microsoft. IBM distributed their version of MS-DOS first as IBM DOS (prior to version 5.0), and later on as IBM PC-DOS.


MS-DOS 1.x

  • MS-DOS 1.20 - Internal version from 1981
  • MS-DOS 1.21 - Internal version from 1982
  • MS-DOS 1.22 - Internal version from 1982
  • MS-DOS 1.23 - Seattle Computers OEM
  • MS-DOS 1.24
  • MS-DOS 1.25 - Corona (BIOS 1.03 and 1.07), Zenith ( 1.19 for the Zenith Z-100 PC Compatible series from 1984 and 1.20 for the Zenith Z-100 from 1982) and Sanyo OEM, Seattle Computers OEM ( 1.17 as part of the released MS-DOS 1.1 source package), and Columbia OEM (Rel. 2.11)

MS-DOS 2.x

  • MS-DOS 2.00 - Apricot, Eagle, NCR, Olivetti (M20 with 8086 add-on), Seequa, Seattle Computers, Tandy and Vector[1] OEM
  • MS-DOS 2.01 - DEC, NEC and Wang Professional Computer OEM
  • MS-DOS 2.02 - Compaq OEM
  • MS-DOS 2.05 - DEC OEM
  • MS-DOS 2.11 - AT&T, BULL, TeleVideo, Olivetti, Toshiba, Apricot, NEC for PC-98xx, NCR, Tandy and ITT OEM
  • MS-DOS 2.11D - Ericsson OEM
  • MS-DOS 2.12 - Compaq OEM
  • MS-DOS 2.13 - Zenith OEM (Z-100)
  • MS-DOS 2.21 - Zenith OEM (Z-100)
  • MS-DOS 2.25 - Same as 2.11, but has better support for Japanese and Korean character sets. Released in October 1985, as stated in a Croatian computer magazine "Moj Mikro".

MS-DOS 3.x

Multi-tasking MS-DOS 4.0

  • MS-DOS 4.00 - A rare OEM version, capable of multi-tasking. Only released by some European OEMs, a working copy can be found online. (Unnamed OEM and Goupil OEM)

MS-DOS 4.x

  • MS-DOS 4.00 - A rare version which was quickly replaced by 4.01 due to bugs. Dated 06/10/1988, a Sampo OEM without disk 6 can be found online.
  • MS-DOS 4.01 - Olivetti, Amstrad, Nokia, Tulip, HP, Toshiba, Zenith and VEGAS OEM
  • MS-DOS 4.02 - Unknown stage, mentioned in PX05132
  • MS-DOS 4.10.20 - International Computer Ltd. OEM version

MS-DOS 5.x

MS-DOS 6.x

The base versions are listed as including 'Enhanced Tools', this means what the retail upgrade is, was sold to OEMs as two packages. These are feature-reduced versions of various Norton utilities. Help was provided through QHelp built into QBASIC.

A separate disk is available of the supplemental files. These are mainly DOS 5 files removed, and random add-ons, such as AcessDOS, Drovak keyboard drivers, and later, DOSSHELL. All versions have them.

MS-DOS 7.x

MS-DOS 8.x

  • MS-DOS 8.00 - Only released as part of Windows ME - XP to Windows 7 inclued a boot-disk in diskcopy.dll