Hello and thanks for your question. I look forward to assisting you today with the best answer possible.
Would you like me to remote in your computer and work directly on this issue?
I'm sorry to say this is the latest version of MAC OS and Canon has not released any driver for MP600 to support this OS.
As a workaround I would have tried to install other canon drivers to see if it makes it run on your OS.
If you don't want to do that you can wait until Canon releases the driver to support MAC OS X El Capitan.