Digital BW, The Print

I am surprised to hear the feeding issues with the 3800. I almost
always feed single-sheet through the Rear Feed using a variety of
papers, from 12 mils thick to 23 mils thick and never get a feed
error. You are supposed to apply firm, consistent pressure on the top
edge of the print and hold it that way until the printer picks it up.
If you continue to see problems, just turn the Paper Size check off
from the front of the printer panel. (Menu -> Setup -> Paper Size)