cartridges, which come equipped with a "CRUM" chip. This chip acts as a counter; once the printer decides the cartridge is "empty," it locks the device, even if there is still physical toner left. Users found that even refilling the toner manually wouldn't work because the chip remained "locked". The "Fix" Movement

For the advanced firmware fix, you need specific information from your printer—the serial number, firmware version, and CRUM number. However, a locked printer may refuse to print these reports. If you are dealing with a standard functional printer, you can obtain this data manually. If the printer is locked, you will need to proceed to the PC method.

Insert any compatible or refilled toner cartridge. The error message should disappear. Print a test page.