I just replaced the toner cartridge and the LCD continues to display the message "Toner Life End" or "Replace Toner".

What is the difference between the toner cartridge and the drum unit?

I print mainly black and white documents. How can I stop the life of my colour toner cartridges from decreasing when I print?

Replace Drum

Replace PF Kit xx

Replace Fuser

I still receive the error message "Replace DrumX" or "Drum End SoonX" after I replace the drum unit with a new one.

Replace Belt

Replace WT (waste toner) Box

Replace Toner