Supplies_ 87A toner cartridge has reached its estimated cartridge life. The printer stopsprinting. Also, the Smart Panel program window appears on the computertelling you to replace the cartridge (See "Using the Smart Panel program"on page 69).At this stage, the toner cartridge needs to be replaced. Check the modelnumber for the toner cartridge used in your machine (See "Availablesupplies" on page 86).Samsung does not recommend using non-genuine Samsung tonercartridge such as refilled or remanufactured. Samsung cannotguarantee non-genuine Samsung toner cartridge's quality or damagesit can cause to the machine. Also service or repair required as a resultof using non-genuine Samsung toner cartridges will not be coveredunder the machine warranty.1. Turn the machine off, then wait a few minutes for the machine to cool.2. Press the release button, completely open the front cover.3. Grasp the handles on the toner cartridge and pull to remove thecartridge from the machine.4. Take a new toner cartridge out of its package.5. Pull out the hopper sheet from a new toner cartridge.6. Holding both handles a new toner cartridge, thoroughly rock it from sideto side to evenly distribute the toner.7. Place the toner cartridge on a flat surface as shown below and removethe protecting cover.If toner gets on your clothing, wipe it off with a dry cloth and wash itin cold water. Hot water sets toner into fabric.8. Make sure that the color of the toner cartridge matches the color slot andthen grasp the handles on the toner cartridge. Insert the cartridge until itclicks into place.9. Close the front cover. Make sure the cover is securely latched and thenturn the machine on.If the front cover is not completely closed, the machine will notoperate.Replacing the imaging unitWhen the life span of the imaging unit has expired, the Smart Panelprogram window appears on the computer, indicating the imaging unitneeds to be placed. Otherwise, your machine stops printing.