Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I don't know your printer's model #, but this is the general meaning of the error you are asking about:
The Paper Output tray is blocked, or something about it is 'broken', or perhaps it is simply closed.
Remove any object in front of the Paper Output Tray, and open the Paper Output Tray.
Then, turn the power Off, and wait 2 minutes or more.
Then after that interval or longer, turn the power On again.
If that does not help clear the error, then you may need to have the printer serviced. (If it less than a year old, Canon should fix it for free, under warranty terms.)