Before changing anything, click the button at the top. This reads all printer data.
IP2700, IP2770, IP2772, IP3600, IP3680, IP4700, IP4800, IP4810, IP4840, IP4850, IP4900, IP4910, IP4940, IP4970, IP4980, IP4990, IP5200. Canon Printer Service Tool V3600
Releasing the Reset button while continuing to hold Power, then pressing Reset five times (or twice, depending on the model). Before changing anything, click the button at the top