Canon imagePROGRAF PRO-300 13" Photographic Inkjet Printer - Manual (Page 572)

Multi-Purpose Tray Jammed
Pull out the multi-purpose tray gently.
If the multi-purpose tray cannot be pulled out, cycle the power switch. The multi-purpose tray will
automatically be ejected.
When the multi-purpose tray is pulled out, place the multi-purpose tray (marked A) again and retry
printing. For more on placing the multi-purpose tray, see
Placing a Printable Disc .
If the multi-purpose tray is still jammed, check if there is a problem with the printable disc.
Multi-Purpose Tray Does Not Feed Properly
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