Canon MX 860 scanner won't work after installing Mt Lion

After upgrading my IMac to Mountain Lion v 10.8 my wireless Canon MX 860 scanner function won't work. The printer works. When I try to start the scanner either from the keyboard or the scanner I get an error message: MP Navigator EXquit unexpectedly.

I downloaded and reinstalled the scanner driver

mac-mx860-14_11_4a-ea8_2-1.dmg

and restarted and it still doesn't work.

any other suggestions?

thank you