Brother HL-4040CN User Manual page 171

Examples of poor print quality
Curled or wavy
Recommendation
Check the paper type and quality. High temperatures and high humidity will
cause paper to curl. (See About paper on page 6.)
If you do not use the printer often, the paper may have been in the paper tray
too long. Turn over the stack of paper in the paper tray. Also, fan the paper
stack and then rotate the paper 180° in the paper tray.
Follow these steps:
a
Open the back cover.
b
Push the gray lever to the right as shown 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 lever
back to the original position.
Troubleshooting
7
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