IBM 5150

21 This message is displayed:
Insert first diskette in drive A
Strike any key when ready
22 Press a key.
Your DOS Diskette back-up is one
of the diskettes you
want to compare and it is already in the drive.
23 Now this message appears:
Insert second diskette in drive A
Strike any key when ready
Do this:
23A Remove the back-up diskette.
23B Insert the DOS Diskette.
23C Press a key.
DOS 3-28