DOCUMENT:Q105183  21-NOV-1999  [msdos]
TITLE   :Backup Overwrites DoubleSpace-Compressed Floppy Disks
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:6.2,6.22
OPER/SYS:
KEYWORDS:

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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 try to back up to a DoubleSpace-compressed floppy disk using Microsoft
Backup or Microsoft Backup for Windows, you receive the following message:

   You have inserted a diskette which contains existing directories and files.
   Please insert an empty diskette or choose "Overwrite" to use the current
   diskette.

   Partial file list
   dblspace.000
   readthis.txt

NOTE: If you choose "MS-DOS Drive and Path" instead on drive A or drive B, you
receive the message "insufficient disk space in <drive letter>: Backup to
DOS path cannot be completed."

CAUSE
=====

Microsoft Backup writes over your DoubleSpace-compressed floppy disk, making it
an uncompressed disk.

Since Backup compresses data, there is no benefit to writing compressed data to a
compressed disk. Once the data has been compressed once, it cannot be compressed
again.

WORKAROUND
==========

You may be able to work around this problem by choosing MS-DOS Path for your
destination.

Additional query words: MWBackup 6.20

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

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