Floppy Disk Drive Lights Flash Under MS-DOS 6.2 (105257)

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 Q105257


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.

When you start some software packages under MS-DOS 6.2, the floppy disk drive lights may flash.


This situation occurs when a software program (for example, Microsoft Anti-Virus, GEO Works Ensemble (GEOS), or a terminate-and-stay- resident (TSR) program loaded in memory calls the Int 21h Function 44h Get Device Parameter IOCTL. This IOCTL causes the DoubleSpace Automount code to check the floppy disk drives for possible DoubleSpace-compressed floppy disks.

The following list includes some of the applications that make this call that otherwise would not access the floppy disk drives:

Norton Desktop for Windows
Central Point PCTools Data Monitor (DATAMON.EXE)

This situation does not occur with earlier versions of MS-DOS, nor does it occur if the DoubleSpace Automount switch is disabled.


You can either ignore the floppy drive light indicators when you start applications or you can disable the DoubleSpace Automount switch.

To disable the DoubleSpace Automount switch, type dblspace /automount=0 at the MS-DOS command prompt, press ENTER, and then press CTRL+ALT+DEL to reboot your computer.

Modification Type: Major Last Reviewed: 11/22/1999
Keywords: KB105257