Error Code 1660 has to do with the Canon ink cartridges indicating that 1 or more cartridges are not installed Properly and so the printer is not able to recognize them to work.
Remove all cartridges and make sure that the chips are clean for all and Reinstall them one at a time making sure the cartridges sits well into the respective slots.
If a cartridge is empty it will need to be replaced with a new one.
Finally press the Resume or the Cancel button to continue your printing process. Ensure that the Canon Printer Error Code 1660 no longer shows up.
If you still see it, Please contact us via email for Support.