No matter what you use your HP LaserJet 5550 for, making the most of every toner cartridge can save you money. Toner cartridges are expensive, and squeezing the largest number of printouts out of each one is one of the best ways to save money without compromising quality. The HP LaserJet 5550 is designed to flash a "Toner Low" message when the cartridge begins to run low, but you can squeeze a few days' more life out of the cartridge by resetting the count.
Lift the toner cartridge cover and pull the toner out of the printer. Shake the toner cartridge vigorously to redistribute the toner inside the cartridge.
Reinsert the toner cartridge in the printer and close the door. Watch the control panel carefully until you see the "New Toner Cartridge" message.
Use the item button to change the setting from "N" to "Y." This tricks the HP 5550 into thinking you have installed a new toner cartridge, resetting the toner count and allowing you to continue using the printer until the toner is truly too low to produce quality content.
Watch the printouts and replace the toner cartridge when the quality begins to deteriorate. Depending on how often you use the LaserJet 5550 and what type of documents you print, you might be able to squeeze a few days to a week out of each cartridge by resetting the toner count.