An image forming apparatus includes a display and a control device. The control device functions as: a detector detecting a trouble occurred in an own apparatus; and a controller. The controller performs, with respect to a trouble-displaying image including a two-dimensional code in which a storage location on a network is converted into an image, at least one of three outputs of displaying on the display, printing on a recording sheet, and transmitting to an external apparatus. The storage location is where information indicating a method for dealing with the trouble detected by the detector is stored. Based on a predetermined first degree using at least either difficulty in solving the trouble or seriousness of the trouble as an indicator, the controller changes a size of the two-dimensional code corresponding to the trouble so as to be larger as the first degree becomes higher, and then outputs the two-dimensional code.