Brother HL-3140CW User Manual page 190

Troubleshooting
Examples of poor print quality
Envelope Creases
Recommendation
 Make sure that the envelope levers inside the back cover are pulled down to
the envelope position when you print envelopes.
See Loading paper in the Manual feed slot on page 12.
NOTE
When you have finished printing, open the back cover and reset the two gray
levers back to their original positions (1) by lifting them up until they stop.
1
5
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