I would unplug the scanner and uninstall the software for it. I would then do a Safe Mode cleanup:

http://www.usbman.com/Guides/Cleanup%20Device%20Manager%20Safe%20Mode.htm

Restart and follow Canon's instructions to the letter to reinstall it.

Bill

: Canon 1220U scanner that I've had running with no problems for the past several months suddenly stopped working. I uninstalled the driver and scanner software so as to get a clean reinstall. Plugging in the usb cable (to either port, both of which work fine with HP 930 inkjet)resulted in an 'unknown device' and I have been unable to replace the resulting generic driver with the one from the Canon CDROM or one downloaded from Canon's site.

: My machine uses the Intel AB/EB host controller on an HP Pavilion 8570C - diagnostic software found on this site reports that the controller is running fine. I only use the two usb ports that came with the machine. Canon emailed me a nice set of clear troubleshooting procedures but that I went through step by step but that didn't help.

: I'm not sure exactly when scanner stopped working, but in the past week or two the following events have occurred (not necessarily in the order stated):

: * Pavilion memory upgraded from 96 to 192 MB
: * Homelink phoneline network card and software installed (network not working yet, either)
: * nimda virus eliminated with the help of Norton's tool
: * klezmer viruses eliminated with the help of Norton's tool. (machine seems clean now).
: * 2 minute power outage uccurred. Computer continued to run fine on UPS -- scanner gets its power from computer via usb.

: As you can see it's been an interesting week. Can someone tell me how to get this scanner running again?
: