my wifes macbook is not able to upgrade to mt lion, but my imac did
we share a canon Pixma pro 9500 printer which works ok on lion with her macbook
but will not install on my imac --even tho I download the latest driver from canon
which they claim supports 10.8
when i run install it claims the software cannot be found on update
iMac, OS X Mountain Lion (10.8.2), canon pixma pro 9500
The driver from Canon does support 10.8. It will be the same driver that Apple has available via Software Update, which by the sound of your post, your Mac is trying to locate the driver from there instead of using the driver that is already installed.
One action you could take is to open Finder and navigate to HD > Library > Printers > Canon. Here you will see the BJPrinters folder. You can trash the contents of this folder and then restart your Mac. After logging back in, try to add the printer again and see what happens.
my pixma pro 9500 will not set up on mt lion
