Euraka! Someone on another site suggested that I donwload the driver from Canon's Canadian site and that did the trick.
Interestingly the file name is exactly the same as the file downloaded from Canon USA but the Canadian verison installed faultlessly while the US version would not install.
In case anyone else ever has this issue and finds this thread, after installing I restarted the G4 and it hung up at the opening Apple logo screen. But after a full power down and restart all was well.
Thanks to all for trying to help.
Mark
My printer somehow became uninstalled overnight, and Canon suggested that I reinstall the drivers. The actual error message is to check that the printer is connected. I repowered both computer and printer, changed the USB cable and repaired the permissions twice.
I downloaded the drivers but when I click on the downloaded file I get an error message that the disk image failed and the volume will not mount. No idea how to fix this and would appreciate any help.
My wife's old G4 with 10.4.11.
THanks.

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