How to install a Canon MX860 on MacBook Pro running MacOS 10.12.4?
You'll need the applications:


Canon IJ Network Tool - this configures the printer/scanner on your for network operation. You can do the initial configuration via USB. It also starts upon login and presents you with a dialog to choose the printer/scanner via its MAC address. It is from the package file mnt_-mac-4_7_0-ea21_3.dmg.
MP Navigator EX 2.1 - this allows you to scan over the network; both scan from the app and from the device's control panel. This is from the package file mnve_5_0-mac-all-5_0_4-ea11.dmg. I've found that version 5.04 of this application does not work on High Sierra (10.13.3). YMMV of course.


Both are available on the Canon support site - https://www.usa.canon.com/internet/portal/us/home/support/details/printers/support-inkjet-printer/mx-series/pixma-mx860/ from the "Drivers &amp; Downloads" tab -> "Software" sub-tab. Note for 2 above, you'll need to "downgrade" the OS version to Yosemite (10.10).