An external device document input and output device connected to a network and using a plurality of communication protocols, the external device document input and output device communicating documents in various data forms to and from a plurality of information devices, the external device input and output device including a first identifying part configured to implement a process of identification so a function of the information device can be used by individual identification; a second identifying part configured to implement a process of identification so a function of the external device document input and output device can be used by individual identification; and a registration part configured to register folders permitted to be used by a user identified by the first identifying part and the second identifying part and register setting information of a recording medium provided in the external device document input and output device, in common media.