Canon Pixma MG6821 Online Manual page 1037

6000
Cause
Printer error has occurred.
What to Do
If the paper is jammed, remove it depending on the jammed location and cause.
List of Support Code for Error (Paper Jams)
Turn off the machine and unplug it.
Plug in the machine again and turn it back on.
If this does not solve the problem, contact your nearest Canon service center to request a repair.
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