Canon TS3100 Series Online Manual page 357

168A
Cause
FINE cartridge is not installed properly, or FINE cartridge not compatible with this printer is installed.
What to Do
Retract the output tray extension and the paper output tray, open the cover, and then remove the FINE
cartridges.
Make sure the FINE cartridge compatible with the printer is installed.
Then install the FINE cartridges again.
Replacing a FINE Cartridge
Push up the FINE cartridge until it clicks into place.
After installing, close the cover.
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