Canon imagePROGRAF PRO-300 13" Photographic Inkjet Printer - Manual (Page 124)

7. Slide right paper guide (G) to align both paper guides with both sides of the paper stack.
Do not slide the paper guides too hard against the paper. The paper may not be fed properly.
Important
• Always load paper in the portrait orientation (H). Loading paper in the landscape orientation (I)
can cause paper jams.
Note
• Do not load sheets of paper higher than the load limit mark (J).
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