Canon LBP-1760 User Manual page 53

Is the stack straight? Do not place the envelopes on the tray at an angle.
Are the flaps of each of the envelopes separate? If the flaps of the envelopes overlap,
paper jams or misfeeds will occur.
The illustrations below show the acceptable and unacceptable arrangement of the
2
flaps of the envelopes in a stack.
Acceptable
The flap of each envelope should be separate, not overlapping the edges of any of
the other envelopes in the stack.
Not Acceptable
If the flap of any of the envelopes overlap the edges of any of the other envelopes
in the stack, like those in the examples below, paper jams or misfeeds will occur.
flaps overlapping
Examples of unacceptable overlapping flaps.
top flap and other flaps overlapping the envelopes underneath
or
top flap overlaps the envelopes underneath
45
Printing Envelopes with the Multi-Purpose Tray