Streaks
You may experience streaks on a printout with a laser printer due to the primary corona wire being dirty. To fix the problem, use a cleaning brush to clean the corona wire.
Creased Paper
If you are experiencing creases on your paper when printing, it could be due to the registration rollers being worn out.
Paper not feeding
If you are experiencing any trouble with the paper not feeding through the system properly, you most likely are experiencing worn out rollers.
Backed up print queue
It is most likely due to large number of print jobs being sent to the printer and the printer cannot handle the workload. Consider using feature such as print spooling to speed your printing.
Faint of ghosted print
You most likely need to replace the toner
Paper Jam
If you get a lot of paper jams, verify that you are using paper of the correct size and thickness. If you are sure that you have the right paper, you could also have a problem with misaligned rollers.
White Stripe
If you have white stripes throughout the printout, your transfer corona wire is most likely the problem. There might be a problem getting the charge to the paper, resulting in toner-missing on the page in areas.
Blank Page
If you have a black page for output, you know there is nothing wrong with the feeder mechanism because the paper is moving through the printer. A blank page indicates a problem getting the toner to the paper, so something is wrong with the corona wires or you have no toner.
Vertical line
A vertical line on the printout typically indicates a scratch in the print drum. You should replace the toner cartridge because it is combined with the print drum. If you replace the toner cartridge and the problem still exists, there could be a problem with the laser.
Toner not fused to the paper
If toner smears off after the page has printed something is wrong with the fuser rollers which might need replacing. Be cautious when working with the fusing components because they are very hot!