1. Choose the same type and high quality substitute carbon powder.
(1) Uniform model
As is known to all, printer toner cannot use the copier toner replacement, with manufacturers of different types of machines cannot mix with each other, after all, every kind of printer toner formula, then affects the print quality, small or damage to the drum unit, cause the machine doesn't work.
(2) Attention to quality
The products on the market often the sham as the genuine, powder quality is bad will directly cause the print effect is poor, but with the enlargement of the market, many professional consumables manufacturer also pay more and more attention to the market, their products are after repeated experiments and then launched, some big brands of printing consumables manufacturer, for example, the quality of the toner like genuine LaserJet Pro M402N Toner is guaranteed.

2. Correct operation method.
Many people, for their convenience, simply make a hole in the powder box, add in the carbon powder, and then tape it. Such an operation could solve the immediate problem, but it could not solve the problem. Often the powder is correct, but the print quality is still not good, is the operation is incorrect. The correct method should be as follows:
(1) Clean the residual powder in the drum.
Because compatible powder not possible and the original powder exactly the same, to avoid trouble, so this step can't avoid, especially original drum add powder to do more for the first time, but if after add powder, and compatible with powder brands and models are exactly the same, you can ignore this step.

(2) Cleaning waste powder in the waste powder bin.
Once filled with waste powder in waste powder storehouse, overflow, will gradually on the printed page will leave vertical black stripes, affect the print quality, is more serious is that it can increase friction, and finally damage the coating on the surface of the drum, drum unit thoroughly to submit an expense account. So be sure to pay attention to cleaning, but be careful not to damage the scraper, it is better to gently knock the waste powder out.

(3) Replacement of necessary accessories.
Take cf226x for example, sometimes added carbon powder print quality is still not correct, a base, and the walls black vertical stripes, selenium drum surface was full of carbon powder, will change the scraper, this is because the deformation of scraper used for a long time already, can't send print when residual powder to waste powder storehouse, but to the paper. In general, the problem can be solved by changing the scraper. There is also a case of the printed copy of the regular black dot, which is that the drum itself has been damaged or severely aged, which requires replacing the drum core.