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Turn the printer off, wait for 5 minutes then turn it back on, does the error return?
Reseat all toner cartridges
CLICK HERE and then press I Agree. A file will get downloaded. Just open/run that file to start the remote desktop session.
Restart the file on your desktop names Elsinor.screenconnect
Then it means that there is some fault with Automatic Density Control (ADC) sensor inside the printer. It may indicate that the sensor is dirty and needs cleaning or is broken and needs replacing. This sensor may also be referred to as a Colour Toner Density (CTD) sensor. Is your printer still under warranty?
You will need to get it repaired and since it is not under warranty, you will charged for the repair. The repair will be expensive.