Canon iX6800 series Online Manual page 451

2100
Cause
The paper size in the print settings and the size of the loaded paper do not match.
Action
Check the print settings and the loaded paper, load paper of the correct size, then press the printer's
RESUME/CANCEL button.
If you want to cancel printing, press the printer's RESUME/CANCEL button again while the POWER lamp
is flashing.
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