MS-DOS 2

MS-DOS 2 is a family of versions of MS-DOS, initially released in 1983.

MS-DOS 2.00
MS-DOS 2.00 was released in 1983-03. It added support for subdirectories, hard drives with a capacity up to 10 MB, and new commands in.

MS-DOS 2.01
MS-DOS 2.01 was released in 1983-11. It added international support via the  command from , where the user can change the time, date and currency formats to suit the country where the user originates. This version also added support for over 7000 Japanese kanji characters.

Other releases

 * MS-DOS 2.01a is the Wang Professional Computer OEM of MS-DOS 2.01, released in 1983. Incorrectly labelled as "MS-DOS 2.10a".
 * MS-DOS 2.05 is the DEC Rainbow OEM of MS-DOS 2.01, released in 1983-10. The DOS kernel  reports version 2.05, but it is simply the MS-DOS 2.01 kernel patched at offset   to report version 2.05.   was also patched to report version 2.11 (originally version 2.10). It was distributed on a single sided high density 5.25" (400KB) disk. It also appears to be patched so MSDOS.SYS does not display the copyright string upon boot.

MS-DOS 2.02
MS-DOS 2.02 was released in 1983-11 as an OEM version for Compaq Plus computers only. As of 2020, it remains to be found.

MS-DOS 2.11
MS-DOS 2.11 was released in 1983-10 by a number of OEMs. In 2014, Microsoft published the source code of this version for the first time.

Source code
Microsoft published the source code of:


 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)
 * (partial)

The OEMs were expected to supply their own  (if they wish to support hard drive),   (for their own machine containing their own copyright strings), a more usable   with a boot sector and any apps they wish to include (,   and etc.). Some OEMs customized this version of MS-DOS to support 720KB 3.5" floppy drives.

Same as earlier versions of MS-DOS, the original non-OEM  binary files contain the string   (from   in the source code).

Interestingly, this version of MS-DOS's  and   reports the same version upon boot.

Other releases

 * MS-DOS 2.11D is the Ericsson OEM of MS-DOS 2.11, released in 1985.
 * MS-DOS 2.11R is a version of MS-DOS 2.11 burned into a ROM chip onto the Tandy 1000 computer models.
 * MS-DOS/Z-DOS 2.13 is the Zenith Z-100 OEM of MS-DOS 2.11, released in 1984.
 * MS-DOS/Z-DOS 2.18 is the Zenith Z-100 OEM of MS-DOS 2.11, released in 1984.
 * MS-DOS/Z-DOS 2.21 is an upgrade for MS-DOS 2.13, released in 1984.

MS-DOS 2.25
MS-DOS 2.25 is the last version of the MS-DOS 2 family. It is unknown when exactly this version was released. Some speculations put the release date in 1985-10.