I'm the guy who generally troubleshoots my printer whenever a paper gets stuck or some signals of despair appear on my printer's LCD screen. When "unconquerable" cases do happen though, I leave it to my repairman on the next block to do the job. If you ask me, a laser
printer dilemma is not at all difficult to deal with. All you need to do is detect the possible cause and consult the manual to see if there's any way you can adjust the printer's parts. At least, that's how a "pro" like me does it.
For instance, if something happens over and over again (e.g., paper jam,
Photoshop images distorted, prints smear, white lines, speckled print, blackened paper), the parts probably need some cleaning up, especially the belts and rollers. Sometimes, you need to replace the cartridge or the fusing rollers, too. If the print appears rough, there's something wrong with the electronic logic circuit. Some parts need continual check-ups but you don't really have to replace them, unless the situation calls for it.
If the image doesn't come out as displayed on your screen, your pickup rollers and drive train are probably in need of replacement. Now this is a sucker: the text becomes distorted. If you encounter this problem, your toner level, scanner, or optical alignment deserve a quick lookover. Your toner level is probably too low or it may even be the result of excessive power supply. Laser printers don't just accept any kind of paper. If your LCD displays a message such as "paper jam" -- check the fuser unit.
