Hi Breasa,
You are correct, the 1660 error is an indication that your PIXMA MG7120 does not recognize one of the ink tanks installed in your printer.
Please make sure that you are only using genuine Canon ink tanks, as we cannot guarantee the compatibility of 3rd party inks.
Please remove the ink tank that is not recognized and look in the slot where it was installed. Make sure there isn't a piece of paper or foreign object or debris near the metal contacts towards the front of that slot.
If you are using Canon ink and there is nothing blocking the metal contacts, please reinsert the ink.
If the 1660 error persists, your PIXMA MG7120 would require service. You are eligible for Canon's Upgrade Program. This is for out of warranty units which have been diagnosed to require service, or for some reason are incompatible with a new or upgraded system. This option allows you a one-time opportunity to purchase a replacement product, discounted from the list price.
To help you get up and running quickly, we also offer free standard shipping (if the order is completed by 12:30PM ET). If you would like to take part in this option, please call our Sales Department at (866) 443-8002 seven days a week, 8am to Midnight. Let them know you have been working with technical support and the Canon Upgrade Program was offered.
