You need to adjust your settings if the printer "thinks" it is out of paper. Even if you have the wrong bond weight of paper, you will have this problem.
On the Home Screen, find "Paper Settings", then you will see a screen with the multipurpose tray and under it will be tray 1.
Choose LTR then choose Plain 1. This is for regular copy paper. If that doesn't work, repeat the steps and choose Plain 2. The weight has to be correct in order for the printer to work correctly, otherwise it will give you the out of paper message.
A4 is close to LTR but is a different size. If you are using A4 paper you must choose A4>Plain 1 or 2 or 3 etc.
I have the MF445dw but this is true for many Canon models.
