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Q104544: Cannot Uncompress Some Floppy Disks Without Removing Data

Article: Q104544
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:6.2,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 21-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 6.2, 6.22 
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SYMPTOMS
========

This information applies to both Microsoft DoubleSpace and Microsoft DriveSpace.
For MS-DOS 6.22, use DRVSPACE in place of DBLSPACE for commands and filenames.

If you compress a floppy disk and immediately try to uncompress the disk, you may
receive the following error message:

  DoubleSpace cannot uncompress drive <letter> because there is not
  enough space on drive <host letter> to hold all of the uncompressed
  files.

  To uncompress drive <letter>, you must remove at least <xxx,xxx>
  bytes of files from either drive.

CAUSE
=====

This occurs because DoubleSpace is very conservative in estimating the space
required to hold the uncompressed files. The estimate is based in part on a
worst-case scenario in which the data on the floppy disk is stored at a 16:1
compression ratio and DoubleSpace must convert the drive from a 16-bit file
allocation table (FAT) to a 12-bit FAT.

RESOLUTION
==========

To work around this problem, remove <xxx,xxx> bytes of data from either
the compressed drive or the host drive.

Additional query words: 6.20 diskette

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS622 kbMSDOS620
Version           : MS-DOS:6.2,6.22

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