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Article ID: 96250 - Last Review: January 11, 2015 - Revision: 2.0

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The procedure for uncompressing a drive differs depending on which version of MS-DOS you are using. If you are using MS-DOS 6.2, run the DoubleSpace maintenance program and choose Uncompress from the Tools menu. If you are using MS-DOS 6.22, run the DriveSpace maintenance program and choose Uncompress from the Tools menu. If you are using MS-DOS 6.0 or you are having difficulty with MS-DOS 6.2 DoubleSpace uncompressing a drive, follow the procedure outlined in this article.

The following procedure describes how to remove DoubleSpace from your hard disk while preserving your files. It is a lengthy procedure and should be followed only if DoubleSpace removal is necessary. If you need to change the size of your DoubleSpace volume, type help dblspace at the MS-DOS command prompt and refer to the Help topic DBLSPACE /SIZE.

If you want to remove DoubleSpace (and all data stored on the compressed drive) but you do not need to preserve your files, DoubleSpace provides a way to delete a compressed drive without manual intervention. You can delete a compressed volume file (CVF) using the DoubleSpace maintenance program interface or the command-line interface. To delete DoubleSpace using the DoubleSpace maintenance program, choose Delete from the Drive menu.

More information

This example assumes that you have compressed your boot drive (C) and that your DoubleSpace host partition is H. For more information on how DoubleSpace assigns host partitions, query on the following words in the Microsoft Knowledge Base:
doublespace and assigns and host
The example also exclusively refers to MS-DOS 6.2 and DoubleSpace. If you are using MS-DOS 6.22, substitute DRVSPACE for DBLSPACE commands, DRVSPACE.* for DBLSPACE.*, and DRVSPACE.SYS for DBLSPACE.SYS.

If you are not removing DoubleSpace from your boot drive, skip steps 2-7.

  1. Back up all the files you want to preserve from your compressed drive (C) by using Microsoft Backup or a third-party backup utility. (For information on using Microsoft Backup, see Chapter 3, "Managing Your System," in the "Microsoft MS-DOS User's Guide.")
  2. When you remove DoubleSpace, what is now drive H will become drive C, which means you will boot from drive H. To be able to boot from drive H and restore your backup files, the DoubleSpace host partition must contain the necessary MS-DOS system files and utilities. Furthermore, if you stored your backup files on a network drive, network redirectors must be available.

    Determine how much free space you will need to copy the MS-DOS files (and network redirectors) on the DoubleSpace host partition (drive H). To do so, use the DIR command. For example, to see how much space is needed for your MS-DOS files, type the following command:
    dir c:\dos
    The output appears as follows:
           194 file(s)    7003143 bytes
                         12959744 bytes free
    The next-to-last line shows the number of bytes used by the files in the DOS directory. This number is the amount of free disk space needed to store the necessary files and utilities after DoubleSpace is removed.
  3. To free unused disk space from the DoubleSpace compressed volume, use the /SIZE switch as follows:
           dblspace /size
  4. Determine how much free space there is on the DoubleSpace host partition. To do this, change to drive H and use the DIR /A command. The last line of the output from the DIR command shows the number of bytes free on drive H. If this number is greater than the number you found in step 2, there is enough space to copy the necessary files and utilities, and you can proceed with step 6. If there is not enough space on the DoubleSpace host partition, proceed to step 5.
  5. Delete enough files on drive C to create the needed space you determined during step 2. (Note: Do not delete any MS-DOS or network files; those files must be present during this procedure.)

    You can use the DELTREE command to do this. (DELTREE quickly deletes entire directories.) For example, to remove the WORD directory and all the files and subdirectories it contains, type the following:
    deltree /y c:\word
    After you delete some files, shrink the DoubleSpace volume file again by typing the following:
    dblspace /size
    To find out if you've created enough free disk space, change to drive H and use the DIR command. Again, the bytes in use and bytes free are displayed. If the last line, "bytes free," shows enough free disk space, continue with step 6. Otherwise, repeat step 5.
  6. Copy all the MS-DOS and network files that you need (the files you determined were necessary during step 2) to the DoubleSpace host partition (drive H). To preserve the file and directory structure, you can use the XCOPY command with the /S switch. For example, to copy all the MS-DOS files into a DOS directory on H, type the following:
    md h:\dos
    xcopy c:\dos\*.* h:\dos /s
  7. Make sure there is a copy of COMMAND.COM in the root of the DoubleSpace host partition by typing the following:
    dir h:\
    If COMMAND.COM is not present, copy it from the boot drive (C) with the following command:
    copy c:\ h:\
    Repeat this step for AUTOEXEC.BAT and CONFIG.SYS files. These files need to be in the root of the DoubleSpace host partition as well.

    You now have all the files you need to boot from the uncompressed drive and restore your backup files; you can begin removing the DoubleSpace volume.
  8. Switch to the root of the DoubleSpace host partition by typing the following:
  9. Delete the DoubleSpace files by using the following command:
           deltree /y dblspace.*
  10. If you are removing DoubleSpace from your boot drive, open the CONFIG.SYS file from the DoubleSpace host partition (H) in a text editor, such as MS-DOS Editor. If you are not removing DoubleSpace from your boot drive, open the CONFIG.SYS file from drive C. Remove any reference to DBLSPACE.SYS. For example, change your DBLSPACE.SYS DEVICE command to appear as follows:
           rem device=c:\dos\dblspace.sys
  11. Restart your computer by pressing CTRL+ALT+DEL.
  12. Restore your backup files.
DoubleSpace has now been removed from your system.

Applies to
  • Microsoft MS-DOS 6.0 Standard Edition
  • Microsoft MS-DOS 6.2 Standard Edition
  • Microsoft MS-DOS 6.22 Standard Edition
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