BACKUP Fails When Writing Log File to Unformatted Disk (72132)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0

This article was previously published under Q72132


The BACKUP command in MS-DOS version 5.0 does not work correctly when the destination disk is unformatted and you try to write a log file to that unformatted disk.


BACKUP appears to be trying to write the log file to the destination disk before formatting the disk. For example, the following command results in an error if the disk in the destination drive is unformatted:

backup c:\dos5\*.exe a: /f:360 /l:a:\backup.txt

The disk in drive A spins for a short time, at which point the following message is displayed:

General failure error reading drive A
Abort, Retry, Fail?
Choosing each of the three options produces different behavior:

    Choosing Abort causes the program to be successfully aborted.
    Choosing Retry causes the error to be repeated.
    Choosing Fail results in BACKUP asking for a disk to be inserted into drive A and produces the following message:

    WARNING! Files in target drive A:
    A:\ root directory will be erased
    Press any key to continue . . .
    After a key is pressed, the FORMAT command is invoked, and the disk is successfully formatted. The following message then appears:

    ***Backing up files to drive A:***
    Diskette Number: 01

    It is quickly followed by the message:

    Error opening logfile
    At this point, the BACKUP program terminates and the DOS prompt appears. The disk in Drive A has no files and contains a label of "BACKUP 001".

Modification Type: Major Last Reviewed: 11/23/1999
Keywords: KB72132