Canon PIXMA TS7700i Series Manual page 518

1687
Cause
FINE cartridge is not installed properly.
What to Do
Open the scanning unit / cover to open the ink cartridge locking cover, and then remove the FINE
cartridges.
Make sure that the FINE cartridges are compatible with this printer and reinstall them.
Press down the ink cartridge locking cover until it clicks into place.
And then, close the scanning unit / cover.
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