Abstract: A counting device for counting a number of image forming operations of an image forming apparatus. The counting device includes a registering device for registering a plurality of identification codes and a comparing device for comparing an identification code stored in a portable memory card with the plurality of identification codes registered in the registering device. A first memory counter counts a number of image forming operations of the image forming apparatus when the comparing device matches the identification code stored in the portable memory card with at least one of the plurality of identification codes registered in the registering device. A second memory counter counts a number of image forming operations of the image forming apparatus when the comparing device does not match the identification code stored in the portable memory card with any of the plurality of identification codes registered in the registering device.

Abstract: An image forming apparatus comprises an inner memory, first checking means, second checking means, a mode selector, judging means and a portable memory. The portable memory is adapted to be connected to the main body of the apparatus and memorizes a portable memory identification number to identify the same portable memory and a plurality of usable apparatus numbers to represent usable image forming apparatuses which become usable by the connection of the same portable memory. The inner memory memorizes an apparatus identification number to identify the image forming apparatus and a plurality of acceptable portable memory numbers to represent portable memories acceptable for the same image forming apparatus. The first checking means checks if the apparatus identification number coincides with any of the usable apparatus numbers, and the second checking means checks if, the portable identification number coincides with any of the acceptable portable memory numbers.