Usually the type of brand of paper you use is not as important as how many pounds it is rated at. With multi-function copier’s, it is recommended that you us 20 pound or 25 pound paper. This is the paper that you should be putting in your cassette trays. Any higher or lower poundage paper will cause paper jams or excessive wear on the pick-up rollers and paper path assembly’s or just strange problems. Resume paper or heavy stock and envelopes should be used with the multi-purpose tray located on the side of the copier.