Thank you for your reply. I finally got the drivers to work, but that is a short-term fix as my High Sirra laptop is from 2013.
I will try VueScan.
As I get a new MacBook Air, I was thinking of getting the Epson Perfection V600, which is also supposed to do a great job in scanning 35mm slides.
Not sure why Cannon gave up on the 9000 series.