1. A method of distributing image data, comprising: detecting image data newly stored in a designated storage area, the image data being received via a network; controlling a distribution system so as to cause the distribution system to process the newly stored image data using a function of a plurality of functions of the distribution system, the function being previously associated with the designated storage area in which the image data is stored, the image data being automatically processed by the function when the image data is detected and a match exists between sender information of the received image data and authorized sender information indicating a sender authorized to use a distribution function of the distribution system; obtaining a charge fee that depends on the previously associated function that is used to process the image data stored in the designated storage area; storing, in a memory, association information that associates sender information of the authorized sender with the authorized sender information indicating the authorized sender; and determining whether the sender information of the received image data matches the authorized sender information, based on the association information and the sender information of the received image data to generate a determination result, wherein the match between the sender information of the received image data and the authorized sender information is based on the determination result.