Brother HL-4040CN User Manual page 172

Examples of poor print quality
Envelope Creases
Recommendation
a
Open the back cover.
b
Pull down the two gray levers, one on the left-hand side and one on the
right-hand side, to the envelope position as shown in the illustration below.
c
Close the back cover and re-send the print job.
Note
When you have finished printing, open the back cover and reset the two gray
levers back to the original position.
Troubleshooting
7
7
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