I don't think this is actually an issue with the OS, per say. It's more then likely a registry issue, what I would do, in case you have not done so yet, is either use a free registry cleanup utility such as
Registry Mechanic 5.0 , or a Commercial product such as
Norton System Works 2005 , and first clean out that registry, next DELETE the uninstall program for the printer,reboot your PC, and clean the registry again so that any reference to the uninstall program being present, will not be in the registry.
This will give you a CLEAN INSTALL of the drivers.
Sometimes you can also get by, when installing CANON DRIVERS, by MANUALLY installing them in the device manager, sometimes however, to install the device, you may be REQUIRED to use a setup program anyways.
When windows sees the .INF file it needs for the printer/scanner driver, the .INF might be written to say... "RUN THE SETUP PROGRAM"..
Which is usually the case in most recent Canon equipment that I have worked with.
So I would DEFINITLY do it the right way, and fix the registry first and reinstall with the setup.
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