Canon MF4780w prints fine from iOS devices, but not the computer

I have a couple of suggestions which may be helpful.

• It is important to confirm that the driver being installed is specifically compatible with and will work with the Mac's currently installed operating system. Sometimes an older system driver will work, but only sometimes. If one is not available for download, ask Cannon when one is to be released.
• When you are able to install a verified compatible driver, then delete and reinstall the printer in your System Preferences.

Give this a try: boot into Safe Mode according to How to use safe mode on your Mac and test to see if the problem persists. Reboot normally and test again.

NOTE 1: Safe Mode boot can take up to 3 - 5 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

NOTE 2: if you have a wireless keyboard with rechargeable batteries connect it with its charging cable before booting into Safe Mode. This makes it act as a wired keyboard as will insure a successful boot into Safe Mode.

If the above doesn't help try this: Reset the Mac printing system to solve a problem - Apple Support

I say "verified" because some people assume that if they download the latest driver it will work. I wanted to make clear that the driver has to be written to work with that specific operating system. Since you have done all that, you might consider working with Canon's support people to try to identify what the issue is.