Using MS-DOS Shell to Format Low-Density Disks (49717)

The information in this article applies to:
    Microsoft MS-DOS operating system 4.0
    Microsoft MS-DOS operating system 4.01
    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 Q49717


The MS-DOS Shell's "DOS Utilities" title list contains a FORMAT command. If you select this utility, the MS-DOS Shell displays a dialog box and a default parameter, of "a:". This is documented on Page 33 of the "Microsoft MS-DOS Shell User's Guide" manual for version 4.0.

If you have a high-density drive (that is, 5.25-inch 1.2 MB or 3.5-inch 1.44 MB) and high-density floppies, you should just press the ENTER key. If you have a low-density drive, this is not a concern because only low- density disks can be used. You just need to be careful within the MS-DOS Shell or at the command line when using low-density disks in a high-density drive. You usually won't need to change the default of "a:".

In the above situation, you must add to the "a:" default an extra parameter to format low-density disks in a high-density drive. For 5.25-inch 360K disks, the parameter is /F:360K. For 3.5-inch 720K disks, the parameter is /F:720K. This makes the dialog box display either "a: /F:360K" or "a: /F:720K", depending on disk size.

Changing parameters in a dialog box is often forgotten while using the MS-DOS Shell, since the MS-DOS Shell allows you to point and click without typing, and in many cases without any need for documentation.


If you have a high-density disk drive and format both low-density and high- density disks in the drive, you can avoid this problem by adding a program with a title similar to "Format low density" that would format a disk with the "/4" option.

The default MS-DOS Shell command definition for the FORMAT command is as follows:
   format [/t"Format Utility"/i"Enter drive to Format."/p
          "Parameters . .  "/d"a: "/r]||pause||
The line above has been split immediately following the "/p" parameter, but should fit on one line. The ||'s above are generated with the F4 key.

To make a "Format low density" program entry, just copy the entry to a new entry, change the program name, then change the program's command options. The string in quotation marks following "/t" can be changed to "Format low density Utility", and the string following "/d" can be changed to "a: /F:360K" or "a: /F:720K", depending on disk size.

Modification Type: Major Last Reviewed: 5/12/2003
Keywords: KB49717