An image forming apparatus registers a message using a microblogging function in a Web server. When the image forming apparatus confirms a comment to the registered message, it analyzes the comment and converts it into control information for executing processing by the image forming apparatus. The image forming apparatus generates an analysis result comment for confirming whether or not the analysis result is correct, and registers the analysis result comment in the Web server. When a comment of the user to the registered analysis result comment is affirmative, processing in accordance with the control information is executed.