The Service Tool V3400 allow you to reset ink counter for some Canon printers. If the window of the servie tool is inactive, try these solutions:
- Power off the printer
- Plug the power cable in another USB port
- Restart the procedure: http://fix-your-printer.blogspot.fr/2016/02/service-tool-v3400-for-resetting-canon.html
- Disconnect the USB cable from the printer
- Wait a few seconds and power back the USB cable
- On Windows, click "next" when appears "New peripheral"
- Open the service tool and the reset