Canon MG7700 Series Online Manual page 768

Disc Tray Jammed
Pull out the disc tray gently.
If the disc tray cannot be pulled out, turn the machine off and turn it back on again. The disc tray will
automatically be ejected.
When the disc tray is pulled out, place the disc tray ("J" is on the upper side) again and retry printing. For
more on placing the disc tray, see Placing a Printable Disc.
If the disc tray is still jammed, check if there is a problem with the printable disc.
Disc Tray Does Not Feed Properly
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