Brother MFC-7820N - Manual (Page 106)

Chapter 11
11 - 19
Curl or wave
Check the paper type and quality. High temperatures and high humidity will cause
paper to curl.
If you don’t use the MFC very 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.
Wrinkles or creases
Make sure that paper is loaded properly.
Check the paper type and quality. (See About paper on page 1-9.)
Turn over the stack of paper in the tray or rotate the paper 180° in the input tray.
Examples of poor print quality Recommendation
B DEFGH
abc efghijk
A C D
b c d e
1 3 4