Back in the day, when a printer reached its internal "page limit," it would effectively lock itself to prevent ink from leaking out of the waste pads. While manufacturers wanted you to send the unit to a service center, the became the "skeleton key" for hobbyists. It allowed users to:
The (also referred to as ST1050 or Version 1050) is a proprietary software application developed by Canon for authorized service centers. Unlike the consumer-grade drivers and utilities available on Canon’s official website, this tool operates at a firmware level. canon service tool 1050.exe download