MS-DOS Updates

Only MS-DOS 6.x received updates for upgrading to the current point release. Some other releases got minor updates to various utilities to fix problems.

MS-DOS 7.0

OLDDOS.EXE - MS-DOS 7.0 Supplemental files (16 August 1995)

MS-DOS 6.x

Microsoft released free updates via ftp.microsoft.com for upgrading licensed users from their current 6.x version of MS-DOS to the latest version at the time. No upgrade to MS-DOS 6.21 from prior versions was released as 6.21 was just 6.20 with disk compression removed for legal reasons.

Target Version	From Version(s)	Date	Download	Readme	Notes
6.20	6.0	30 September 1993	stepup.exe	Readme	Upgrades from MS-DOS 6.0 to 6.20
6.22	6.0, 6.20, 6.21	30 May 1994	stepup.exe	Readme	Upgrades from MS-DOS 6.0, 6.20 or 6.21 to MS-DOS 6.22. For non-english versions of MS-DOS, you can grab this update from here. If you were previously using DoubleSpace, you may want DBLCONV.EXE too - this lets DOS 6.22 read DoubleSpace volumes and upgrade them to DriveSpace.

Supplemental Utilities

MS-DOS 6.0 Upgrade FAQs

MS-DOS 6.0-related

PD0805.EXE — SMARTDrive 4.2 - offers more conservative disk caching (with slower disk write performance) than the SMARTDrive 4.1 included with DOS 6.0

MS-DOS 5.0

PD0646.EXE — For MS-DOS 5 Upgrade 5.0: Updated chkdsk.exe and undelete.exe files (replaces files dated 04/09/91)
PD0489.EXE — MS-DOS 5.0 Messages reference

MS-DOS 4.x

Date	Download	Readme	Notes
8 September 1992	PD0255.EXE	Readme	Patch for MS-DOS 4.00/4.01 to correct handling of 32 MB Files. Also includes updated FASTOPEN.EXE, FORMAT.COM and GRAPHICS.COM. For retail/packaged versions of MS-DOS 4.0, 4.01 and 4.01a only - may not work on OEM-modified versions of MS-DOS.

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