1) Remove machine from the box (If not already done).
2) Open the front door and remove the drum to avoid any possible scratches.
3) Locate the black tab in the rear of the machine, located just below and to the left of the white TD drive gear.
4) Use your finger or a flat blade screwdriver to simply pop out the black tab.
5) Install the drum and toner cartridge.
6) The machine will now accept DM or the AR Toner/Developer cartridge.