Canon PIXMA MG5721 User Manual - Page 921

"No ink"/"Ink cassette error" "Ink Error" "Hardware Error" "Printer error" Check the support code on the LCD and take the appropriate action to resolve the error. List of Support Code for Error Check the support code on the LCD and take the appropriate action to resolve the error. List of Support Code for Error Check the support code on the LCD and take the appropriate action to resolve the error. List of Support Code for Error An error requiring servicing may have occurred. Turn off 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. 921