Lexmark W812 User Reference Manual page 41

Symptom
Paper frequently
jams (continued).
Paper jams when
duplexing Universal
size paper.
The Paper Jam
message remains
after you remove the
jammed paper.
The page that
jammed does not
reprint after you
clear the jam.
Cause
The paper frequently jams in the optional
500-sheet tray.
The Universal paper size selected is
outside the range for duplexed jobs.
There is still a jam in the paper path.
Jam Recovery in the Setup Menu is set to
Off.
Solution
Load the paper to the stack height
indicated with an A.
Use paper between 148 mm–297 mm (5.8
in.–11.7 in.) wide and 148 mm–508 mm
(5.8 in.–20 in.) long.
1 Open and close the top cover to clear
the message.
2 Check the entire paper path.
See Clearing jams
Set Jam Recovery
41
for more information.
to Auto or On.