Canoscan 5600f compatibility with Catalina

This is an ancient scanner, and Canon has likely long since stopped issuing drivers for it. They would be 32-bit drivers in any case and incompatible with Catalina. Your recourse is to use the paid, 64-bit VueScan Professional which supports this scanner without any Canon software or drivers. You can download a free trial of VueScan and test it with your scanner.

The last update I can find is version: 4.1.4a for Mojave dated Sep 2018

https://www.canon.co.uk/support/consumer_products/products/scanners/canoscan_series/canoscan_5600f.html?type=drivers&language=&os=macos%2010.14%20(mojave)

If this driver does not install, try Vuescan, there is free test available for the 5600f scanner here: https://www.hamrick.com/vuescan/canon_5600f.html

Gary,

The Canon site does not show any Catalina selection for this driver, or mention support beyond Mojave. It is a 64-bit Image Capture driver (I checked), but whether it is actually compatible with Catalina would remain to be seen by the OP per your suggestion.