The toner cartridge carrier rotates and then stops. After confirming the Insert Black Toner (K) message, open the front door. Hold the tape on the protective cover and gently pull it forward to remove the cover from each cartridge slot. You only have to remove the cover from each toner cartridge slot the first time you use your printer. Toner will be present on the roller. Make sure the color of the toner cartridge matches the slot on the toner cartridge carrier. The order is K, Y, M, C. Gently