Canon TR7500 Series Online Manual page 547

1890
Cause
Tape for securing print head holder during transportation may still be attached.
What to Do
Open the scanning unit / cover and make sure the tape for securing the print head holder during
transportation has been removed.
If the tape is still there, remove it and close the scanning unit / cover.
If this does not solve the problem, contact your nearest Canon service center to request a repair.
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