. In this case, the access controller may permit the first information storage device to access the first removable recording medium when the medium detector detects the second removable recording medium mounted in the predetermined position. According to the invention, since access to the first removable recording medium is permitted when the medium detector detects the second removable recording medium mounted in the second information storage device, a user who does not have the second removable recording medium cannot access the first removable recording medium. Hence, the security provided for information of the first information storage device can be improved. The access 