DIAGNOSIS The printer hasn't recognized the new cartridge. This is almost always a chip communication issue, not an actual toner level problem.
FIX First, reseat the toner cartridge with the printer OFF, then power it on.
- Turn the printer completely OFF and unplug it for 60 seconds.
- Open the front cover, firmly remove the toner cartridge, and reinsert it until it clicks securely.
- Close the cover, plug the printer back in, and turn it on. The initialization process should clear the error.
IF THAT DIDN'T WORK The cartridge's memory chip might be faulty or dirty. Remove it again and gently clean the gold-colored contacts on the cartridge end with a dry, lint-free cloth. Reinstall.
HEADS UP Using third-party or remanufactured cartridges can cause persistent recognition errors even after these steps. The printer is very picky about them.