The present remote support system is provided as an information processing system including an image forming apparatus, an information processing apparatus, and a relay server. The present information processing apparatus obtains a first session ID and temporary authentication information for communicating with the image forming apparatus via the relay server by transmitting a request to the relay server, and the information processing apparatus displays the temporary authentication information on a display. Also, the present image forming apparatus accepts temporary authentication information via user input and uses the temporary authentication information to transmit a request to the relay server to obtain a second session ID for communicating with the information processing apparatus via the relay server.