FORMAT and DISKCOPY Errors with Stacker 3.x (106141)

The information in this article applies to:
    Microsoft MS-DOS operating system 3.2
    Microsoft MS-DOS operating system 3.3
    Microsoft MS-DOS operating system 4.0
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q106141


If you are running STAC Electronics Stacker version 3.0 or 3.1 on your computer, you may receive the following errors when you use the MS-DOS DISKCOPY and FORMAT commands on floppy disks:


Formatting while copying
Drive types or diskette types not compatible
Copy process ended
Copy another diskette (Y/N)?

Existing format differs from that specified
This disk cannot be unformatted.
Proceed with format (Y,N)?


Parameter not compatible with fixed disk.
Format terminated.


Error reading partition table. Format terminated.


Extended error 21. Format terminated.


According to STAC Electronics, these problems are caused by Stacker's AutoMount feature. If you remove a Stacker-compressed floppy disk and insert an uncompressed disk in the same drive, you may be unable to use the MS-DOS DISKCOPY and FORMAT commands on the uncompressed disk until the drive is unmounted. In addition, a Stacker-compressed disk must first be unmounted before it can be formatted with the MS-DOS FORMAT command.


To work around these problems, first unmount the disk drive. This can be done by typing stacker -x: at the MS-DOS command prompt (where <x> is the letter of the floppy disk drive) or by removing the compressed floppy disk from the drive and rebooting the computer.


Stacker 3.0 and 3.1 are manufactured by STAC Electronics, a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability.


"Stacker 3.0 for Windows and DOS User's Guide," pages 137 and 274

Modification Type: Major Last Reviewed: 5/6/2003
Keywords: KB106141