3.5-inch MS-DOS 5 Upgrade May Fail with Early DOS Versions (75087)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q75087


When upgrading to MS-DOS 5.0 or later from DOS versions earlier than 3.2, installation from the 3.5-inch MS-DOS 5 Upgrade disks may fail.

Most MS-DOS and OEM DOS versions earlier than DOS 3.2 do not support 3.5- inch floppy drives and thus will not be able to correctly read all the files on 720K disks. When the Setup command is run from MS-DOS 5 Upgrade Disk 1 - Setup, the message "bad command or file name" will be displayed. When the DIR command is used on one of the MS-DOS 5 Upgrade disks, all the files will not be listed, or the filenames will displayed as garbage (extended ASCII characters).

For example, IBM PC-DOS versions 3.0 and 3.1 will provide the following information with the DIR command:
Setup Disk     Files on Disk      Files Displayed
----------     -------------      ---------------
   1               37                   5
   2               28                   0
   3               52                   27
Other OEM DOS versions may also exhibit the same behavior or display garbage.


To successfully install the MS-DOS 5 or later Upgrade, do one of the following:
    Obtain the 5.25-inch MS-DOS 5 or 6 Upgrade disks if the computer system has a 5.25-inch floppy drive.
    If another computer that is running DOS 3.2 (or later) with 1.2 MB and 3.5-inch floppy drives is available, and the current system has a 1.2 MB floppy drive, do the following:

      Copy all files from each 3.5-inch MS-DOS 5 or 6 Upgrade floppy disk to three 5.25-inch 1.2 MB disks using the second computer.
      Label the disks as Disk 1, Disk 2, and Disk 3 using the LABEL command. There should be six spaces between the word "Disk" and the number in the volume label (for example, Disk 1).
      Run Setup from the 1.2 MB floppy drive on the first computer.

    Start from a later DOS version that supports a 3.5-inch floppy drive, such as MS-DOS or PC-DOS versions 3.2 or later, and run Setup.

Modification Type: Major Last Reviewed: 5/12/2003
Keywords: KB75087