Canon MX520 series Online Manual page 138

When you open the transport unit, support the machine with your hand so that it does not fall down.
7. Pull out the jammed paper slowly.
When you pull the jammed paper, support the machine with your hand so that it does not fall down.
Note
If the paper is rolled up and it is difficult to remove, grasp the edges of the paper, then remove
the jammed paper.
If you cannot remove the jammed paper from the transport unit, close the transport unit, take
back the machine in original position, then open the paper output cover to remove the paper.
Paper Is Jammed inside the Machine
8. Close the transport unit.
Note
After you close the transport unit, take back the machine in original position at once.
9. Plug the machine back in and turn the machine back on.