Certain HP printers are intended to work only with cartridges that have a new or reused HP chip or electronic circuitry. This Printer uses dynamic security measures to block cartridges using a non-HP chip or electronic circuitry. Periodic firmware updates will maintain the effectiveness of these measures and block cartridges that previously worked. Reused HP chips and electronic circuitry enable the use of reused, remanufactured, and refilled cartridges.