In an image processing apparatus, a processor reads a boot loader from a first storage device, reads a main program from a second storage device by executing the boot loader, and, by executing the main program, transitions to an operation state. The first storage device is mounted on a board on which the processor is mounted. The second storage device is electrically connected with the processor via a bus. When an error occurs during reading of the main program from the second storage device, the processor automatically reads a backup program from the third storage device and displays a screen including warning information on a display device by executing the backup program.