Canon LBP7780CX User Manual page 900

7
If the paper is jammed in the area shown in the figure when the optional paper feeder is used, remove
the paper.
(1) Pull out the edge of the paper.
(2) Remove the paper by pulling it gently in the direction of the arrow.
8
While holding the tab (A), open the duplex cover.
9
Remove any jammed paper.
(1) Pull out the edge of the paper.
(2) Remove the paper by pulling it gently in the direction of the arrow.