A process executing system for receiving image data of an output material from an apparatus and processing the output material, the process executing system comprising a communicator and a duplicate detector. The communicator is configured to transmit, in response to a request from the apparatus, to the apparatus, output data of the output material including identification information of the output material, and is configured to receive image data generated by reading the output material by the apparatus, the output material being the output data printed by the apparatus. The duplicate detector is configured to detect a generation of the image data from a same output material as the output material, based on the identification information of the output material attached in the image data received by the communicator.