Backup Overwrites DoubleSpace-Compressed Floppy Disks (105183)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q105183


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
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."


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.


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

Modification Type: Major Last Reviewed: 11/21/1999
Keywords: KB105183