Paper Jam Frequently Asked Questions

Q: What causes constant paper jams?

Q: Why do I have paper jams with one or two PF-5 paper trays, and a DU-1 duplexer? Q: Why do I have occasional paper jams with my stack of two PF-5's and DU-1 duplexer?
OR
Q: Why is the printing skewed when printing from each PF-5 paper feeder? Q: Why do I get paper jams with my PF-7 2000 sheet feeder?