I installed the drum and when I installed the toner cartridge it broke the drum. So I put in another drum, installed another toner cartridge and printer says "replace unresponsive toner", so I put in another toner and now it says "replace unresponsive drum" Printer is like new less than a year old and is junk. I am going with another brand.
Replaced a unit that was at half it's life span. The sponge seal where the toner cartridge set was leaking toner thus was leaving black lines on the printout. The new unit corrected the problem.