DoubleSpace Cannot Mount Compressed Write-Protected Disk

ID: q96200


The information in this article applies to:
  • Microsoft MS-DOS operating system versions 6.0, 6.2
  • Microsoft Windows 95


SYMPTOMS

When you try to mount a write-protected disk with DoubleSpace, you receive the following error message:

DoubleSpace cannot mount drive <x> because the file
<x>:\DBLSPACE.nnn is not a valid compressed volume file.
where <x> is the floppy disk drive letter.

When you try to mount a write-protected removable media disk under MS-DOS 6.2, you receive the following error:
Dblspace cannot mount drive <drive letter>:
The <drive letter>:\Dblspace.000 file is not a valid compressed
volume file. To fix it, type scandisk X:\Dblspace.000 at the
command prompt.


WORKAROUND

To work around this problem, remove the write protection for the disk.


MORE INFORMATION

When DoubleSpace mounts a compressed volume file (CVF), it ensures the Microsoft DoubleSpace BIOS parameter block (MDBPB) (the overall configuration sector) and the BitFAT (a table of available heap sectors) are current. To do this, DoubleSpace must write to the disk. This feature is under review and will be considered for inclusion in a future release.

You can mount a floppy disk by running DoubleSpace, or you can mount the floppy disk with the MS-DOS DBLSPACE /MOUNT command. For example, type the following command at the MS-DOS command prompt and press ENTER if your floppy disk drive is drive A:

dblspace /mount a:
For more information on DoubleSpace, type "help dblspace" (without the quotation marks) at the MS-DOS command prompt and press ENTER.


STATUS

This behavior is by design.

Additional query words: 6.00 6.20 win95 win95x read-only read only drivespace drvspace

Keywords : kbenv kbtool msdos
Version : MS-DOS:6.0,6.2; WINDOWS:95
Platform : MS-DOS WINDOWS
Issue type :


Last Reviewed: November 16, 1999
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