Canon PIXMA TR4520 Online Manual page 559

1890
Cause
Protective material or tape may still be attached to FINE cartridge holder.
What to Do
Open the paper output cover, then confirm that the protective material or the tape does not remain
attached to the FINE cartridge holder.
If you find the protective material or the tape remains attached, remove it, then close the paper output
cover.
If this does not solve the problem, contact your nearest Canon service center to request a repair.
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