Disclosed is a data processing apparatus providing a predetermined function by executing a program for the data processing apparatus, including a first storage unit that stores encoded execution starting data for starting execution of the program; a first decode key storage unit that stores a first decode key capable of decoding the encoded execution starting data; a start up unit that obtains the first decode key from the first decode key storage unit when turning on the power is accepted and decodes the encoded execution starting data by the first decode key to start executing the program; and an authentication confirmation unit that sends a request for authentication to an external apparatus after the start up unit starts executing the program and starts providing the predetermined function when obtaining an authentication result indicating the apparatus is authenticated from the external apparatus.