Message “This Program Must be Run Under DOS and not From a DOS Box” when running Image for DOS Under FreeDOS

Image for DOS is compatible with FreeDOS, but some configurations may result in the message "This program must be run under DOS and not from a DOS Box" when booting from the FreeDOS-based floppy disk.

You can work around this problem by creating a file named AUTOEXEC.BAT on the FreeDOS floppy and putting the following lines in it:

set OS=FD
image.exe

If you are already using an AUTOEXEC.BAT file with some other parameters specified, just add a new line with "set OS=FD" to what you have already. For example, if you already had this in your AUTOEXEC.BAT file:

set IFD=nocan
image.exe

Then simply change it to this:

set OS=FD
set IFD=nocan
image.exe