DoubleSpace Err Msg: DBLSPACE.<nnn> Is Not a Valid CVF (111908)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.2

This article was previously published under Q111908


ScanDisk repairs an error in the Microsoft DoubleSpace BIOS Parameter Block (MDBPB), or does not find any errors, when examining a compressed volume file (CVF); however, DoubleSpace is unable to mount the CVF and displays the following error

DoubleSpace cannot mount drive <x>.
The <y>:\DBLSPACE.<nnn> file is not a valid compressed volume file.
To fix it, type SCANDISK <y>:\DBLSPACE.<nnn> at the command prompt.
where <x> is the drive letter of the CVF when mounted, <y> is the host drive, and <nnn> is the CVF's sequence number (extension). You do not have access to the files on the compressed drive.


There may be rare instances of CVF corruption that ScanDisk cannot correct. Microsoft is researching this problem and will post new information in the Microsoft Knowledge Base as it becomes available.



If you are using MS-DOS 6.2, and your CVF was not created with a beta version of MS-DOS 6.0, contact Microsoft Product Support Services for assistance in resolving this problem. NOTE: If your CVF was created with a beta version of MS-DOS 6.0, you need to remove the DoubleSpace CVFs, and then install an MS-DOS 6.x Upgrade. You will not be able to backup the data on the damaged CVF in this case. IMPORTANT: If you have the above symptoms and are running MS-DOS 6.0, upgrade to MS-DOS 6.2 and use ScanDisk to repair the CVF. ScanDisk can correct most instances of CVF corruption that prevent DoubleSpace from mounting the volume.


To access the files on a compressed drive or CVF, DoubleSpace must mount the CVF. While ScanDisk can correct most problems that prevent DoubleSpace from mounting a CVF, there may be rare cases of CVF corruption that ScanDisk cannot repair.


"Microsoft MS-DOS 6 Programmer's Reference"

Modification Type: Major Last Reviewed: 11/21/1999
Keywords: KB111908