If you've had your printer connected to your Windows machine for a while, it's not unheard of for it to throw out an error message that says "Driver Is Unavailable For Canon Printer" when it's unable to communicate with the driver. This error can make your printer unusable, so it needs to be fixed ASAP. If you can't do it yourself, you might want to reach out to Canon customer support for help. They can provide extra steps for troubleshooting or suggest fixing or replacing your printer.