Is it OK to format 1.4 MB disks in an 800K drive?
—————————————————— No. Apple says you should not format 1.4 MB disks as 800K disks, and notes that media manufacturers do not guarantee the reliability of disks formatted in this manner. If a 1.4 MB disk is formatted in an 800K drive, it will be unreadable by a 1.4 MB drive. Apple recommends returning the disk to a computer with an 800K disk drive, and copying the data to a properly-formatted disk. Another technique that Apple recommends in emergencies is to put a piece of tape over the extra hole on the disk. That should allow the 1.4 MB drive to read the disk. You should then remove the tape and reformat the disk.