Abstract: The present invention provides a magnetic disk inspection method and its system suitable to supply magnetic disks stored in a cassette to a plurality of inspection devices and collects inspected magnetic disks from the inspection devices. The cassette in which uninspected magnetic disks are stored is taken out from a cassette housing unit and transferred to any one of a plurality of optical inspection units. The optical disk inspection unit to which the cassette with the uninspected magnetic disks stored therein is transferred, takes out an uninspected magnetic disk and inspects both surfaces thereof. The magnetic disk whose both surfaces are inspected and which is determined as a non-defective product is stored in a cassette for collecting non-defective magnetic disks. The cassette is transferred from the optical inspection unit to the cassette housing unit. The transferred cassette is housed in the cassette housing unit.

Abstract: A storage medium exchanging device to discharge a movable cell, which is one of plural magazine cells for storing a storage medium inserted from a doorway, and to store the movable cell, include a carrying part on which the movable cell is mounted; and a wrong insertion preventing part which generates discharging force to make the carrying part discharged from the magazine and blocks at least a part of non-doorway of the discharged movable cell.