Though Canon doesn't support the 640, it prints from my Mac 0S 11.1 just fine with USB connection. Will not scan to Mac, either using the printer input or through the Mac options. How can I get the scanner to recognize the computer? IJ? what do I look for, and where??
You are correct, the PIXMA MP640 is not supported with macOS v11 (Big Sur). You are eligible for Canon's Upgrade Program. This is for out of warranty units which have been diagnosed to require service, or for some reason are incompatible with a new or upgraded system. This option allows you a one-time opportunity to purchase a replacement product, discounted from the list price.
To help you get up and running quickly, we also offer free standard shipping (if the order is completed by 12:30PM ET). If you would like to take part in this option, please call our Sales Department at (866) 443-8002 weekdays and Saturdays after 11 AM ET (8 AM PT). Let them know you have been working with technical support and the Canon Upgrade Program was offered.