You probably uninstalled the program that comes along with some Canon printers, but not the driver itself. You need to go to the Control Panel and open the Printers section. Delete the printer from there.
Next, right-click on My Computer and select "Properties". Click the "Hardware" tab, then the "Device Manager" button. Delete the printer from here as well (if it is present).
Next, unplug your printer from your computer and install the drivers. Don't plug it in until the install program asks you to or begins searching for the printer.
If you need any further help or have any questions, please feel free to ask.
