Q74709: Cannot Format High Density Floppy Disk as Low Density

Article: Q74709
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:3.x,4.x,5.0
Operating System(s): 
Keyword(s): 
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0 
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SUMMARY
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When attempting to format a 3.5-inch high density (1.44 MB) floppy disk as a low
density (720K) disk, the following error message may be displayed:

  Invalid Media or Track 0 Bad - Disk Unusable.

This is due to the ability of some floppy drives to sense the media type of
3.5-inch disks. High density 3.5-inch disks have two holes in the disk shell.
Low density 3.5-inch disks have only the write- protected hole. The disk will
format correctly as a 1.44 MB disk.

MORE INFORMATION
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To make a floppy drive recognize a high density disk as a low density disk,
cover the second hole (not the write-protected hole) in the disk shell.

Additional query words: 3.20 3.30 3.31 4.00 4.01 4.01a 5.00 noupd

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401
Version           : MS-DOS:3.x,4.x,5.0

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