Apple File Exchange is a utility included on the Tidbits disk or Install 2 disk in system versions 7.0 through 7.1. In System 7.5, it was replaced by PC Exchange. Apple File Exchange could read floppy disks from Macs, as well as disks from DOS/Windows and ProDOS (Apple II) systems. This utility enabled Macs to read PC disks -- but not without a trick: the diskette must have been inserted after Apple File Exchange was open! If this was not the case, the Mac would complain that the disk inserted "was not a Macintosh disk" and requested initialisation.