Dell 5100cn Color Laser Printer User Manual page 185

7. Grip the levers at each end of the toner cartridge with your fingers, then push down firmly to rotate the levers
forward.
8. Pull the toner seal straight up to remove it.
NOTICE: Pull the toner seal straight up. Pulling the toner seal diagonally may tear the seal.
NOTICE: If it takes more than five seconds until you remove the toner seal after inserting the toner cartridge in
the printer, an error message may appear. In this case, perform step 4 again, or turn the printer off once and then
on again.
9. Replace the top cover by inserting its front side into the printer first.