Abstract: An operating system, when having incorporated data, with a certificate attached, for limiting a function of copying a screen, limits the function of the operating system and when receiving a request for a result of an inspection to determine whether the incorporated data is valid, sends out the result of the inspection in response to the request. An application program makes a request to the operating system for the result of the inspection of the data incorporated in the operating system at startup or return from a background processing. When an inspection result sent from the operating system indicates that the data is invalid, the application program forbids a display control means to display a given screen and instructs the operating system to incorporate a valid data therein. When the inspection result indicates that the data is valid, the application program makes the display means display the given screen.