Canon BJC-3000 - Manual (Page 245)

245 Troubleshooting - Paper Jams or Does Not Feed
Paper does not feed from auto sheet feeder
Check 1 Is the paper too thick?
Thick paper does not feed from the auto sheet feeder. You cannot attempt
to print on paper or other media thicker than 0.6 mm (105g/m
2
).
Check 2 Is the sheet feeder overloaded?
The number of sheets you can load in the auto sheet feeder depends on
the media you are using. The media does not feed correctly if you exceed
the prescribed number of sheets.
Check 3 Did you raise the paper rest?
Before you load media other than envelopes in the auto sheet feeder, you
should always raise the paper rest. If you do not raise the paper rest before
loading, the media does not completely enter the paper feed slot during
feeding.