In the end I created a second partition and put my payload file there. That worked, but before that I tried to extend the FAT12 partition with gparted but my copy (from Ubuntu 21.04) objected and said that FAT12 is no longer supported. The Wikipedia page says that FAT12 goes back to the early 80's, along with Huey Lewis and the News.
_______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user