We use MF 731CDW in our office. It is networked to the wifi. We have two macs that use this printer.
COMPUTER ONE: MacBook Pro 13 inch (early 2015) running Monterey OS12.5. When I added this printer - without downloading any additional drivers - just plug and play - it works fine and sees MANY different paper size options which all work fine.
COMPUTER ONE: MacBook Pro 16 inch 2021 also running Monterey OS12.5. I started by just adding the Canon printer - not downloading any additional drivers just as I did with Computer One. However, on this computer, I can only print letter-sized paper. It won't give me any other options. I've tried on multiple software platforms - same result. No option to choose legal size or any other custom sizes, only letter. I then downloaded the most current drivers for this printer from Canon and installed them and added the MF731CDW again. Same result. I then deleted all existing canon drivers from the Mac and re-downloaded and re-installed those most current drivers again. Always the same result. I can choose letter-sized paper. No option to choose legal size or any other custom sizes.
Any ideas? I feel like I'm in the Twilight Zone?
If you are only able to select letter as the paper size, it looks like the wrong driver is being used or there is a problem with the print settings. The generic driver connections that work with the print should be able to provide some other choices than letter. I would suggest trying to resinstall the recommended drivers from our Support site one more time and performing the install. Once the install is complete, you can click on the apple in the upper left hand corner of the screen and then click on system preferences. Once in system preferences click on Printers and Scanners. In printers and scanners, you can right click on the printer list and select the option to reset the printing system. Once the printing system has been reset, you can click the + at the bottom of the list to try adding the printer again.
If you continue to have issues, I would suggest contacting support at 1-800-652-2666. Our agents would be happy to help.