Other Influences Regarding Paper Jamming

Condition of paper: one of most common causes of paper jamming other than poor quality paper is humidity. Humidity disrupts the integrity of the paper, reduces its strength, and strongly inhibits copy quality.
Its easy to determine if humidity is the cause of your problem. Look at the paper loaded in your cassette if it appears to be uneven or lumpy and bumpy discard it for this is an immediate paper jam. Also old paper that has absorbed humidity and dried out again is also uesless.
Paper can be ruined in as little as two hours time if the copier is not located in a climate controlled office or if you live in such a place as the Pacific Northwest were rain and humidity are common place. I recommend only loading enough paper in your cassettes for one day. In humid climates keep your opened packages of paper sealed in a plastic bag. Keep your cases of paper always with the lid on for the cardboard acts as a moisture barrier.
Proper paper handling: proper paper handling is essential. Settel your paper against a flat surface being careful not do damage the leading edge of the paper. Fan the stack of paper also, this provides a layer of air between each of paper and therefore limits the possibility of miss-feeding or double feeding. Fill the cassete a maximum 3/4 full.
If you still have jamming problems now you can blame the machine!
Machine induced factors causing paper jamming:

• Feed tires / rollers are dirty, glazed, hardened, or worn clean with rubber rejuvenate or replace.
• Separator fingers (fuser pick fingers) are dirty or damaged.. Clean off toner, if damaged replace.
• Fuser rollers worn of flat spots on roller. Causes paper wrinkling / jamming. Replace or call tech.
• Mylar(s) or separator belts damaged. Call service tech.
• Sensors / timing switches are not functioning properly. Call service tech.
• Clutches are not functioning properly. Call service tech.