Q71812: UNFORMAT Does Not Work on Disk Manager Partition

Article: Q71812
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 19-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system version 5.0 
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SUMMARY
=======

Because MS-DOS recognizes only up to 1024 cylinders on a physical hard drive,
the MS-DOS 5.0 UNFORMAT command restores only partitions at or under the 1024
cylinder limit. It does not restore a partition created using Ontrack Computer
Systems' Disk Manager if that partition spans the 1024 cylinder boundary on a
physical hard drive.

MORE INFORMATION
================

If a partition created using third-party partitioning software spans the 1024
cylinder boundary, it will not be restorable using the MS-DOS UNFORMAT command
unless the device driver accompanying the software is first loaded. For example,
it is possible to restore such a partition created using SpeedStor because its
drivers, HARDRIVE.SYS or SSTOR.SYS, can be loaded whether or not a SpeedStor
partition is present.

However, Disk Manager's driver, DMDRVR.BIN, does not load unless there is a Disk
Manager partition detected. Because DMDRVR.BIN does not load, UNFORMAT cannot
look beyond the 1024 cylinder boundary; therefore, you cannot use UNFORMAT to
restore the partition.

The products included here are manufactured by vendors independent of Microsoft;
we make no warranty, implied or otherwise, regarding these products' performance
or reliability.

Additional query words: 5.00

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS500
Version           : MS-DOS:5.0

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