Canon L90 - Manual (Page 171)

Troubleshooting
8-8
11
Lift the paper stack cover and pull
it out completely.
Make sure the back end of the cover does not
catch the front paper guide.
12
Carefully pull jammed paper from
inside the slot.
If you tear the paper, remove any torn pieces
to avoid further jams.
13
Insert the paper stack cover.
Make sure the back end of the cover does not
catch and lower the scanning platform.