Canon MG7500 series Online Manual page 743

1310
Cause
The size of paper may not be compatible with automatic duplex printing.
Action
The sizes of media suitable for auto duplex printing are A4, Letter, A5, B5, and Hagaki. Make sure that the
size of the paper loaded in the machine is correct. Tapping OK on the touch screen will eject the paper
and restart printing from the front side of the next paper. The reverse side of the ejected sheet will not be
printed.
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