An available term of use of the player is set in terms of the number of dates or a playing time. If it is determined by a lock-setting determining unit that the player is lock-set when an optical disk is loaded, the player is lock-released by a lock releasing unit. After the player has been lock-released, if the available term is extended as a result that it is determined by an available term determining unit that the available term has expired or if it is determined that the available term has not expired yet, a playing start processing unit proceeds to processing of starting the playing. If the available term has expired, but should not be extended, the player is lock-set by a lock setting unit.