The computer is a laptop running Windows 7.
The message on the computer is that it does not recognise the USB device.
The error message is on the camera.
The camera is almost 4 years old.
The only message is (405) at the top is says ...Busy.
Same error code
doesn't say busy now
will take battery out now and clean as suggested
presumably I can contact again tomorrow if not successful
OK I have tried your advice - twice , with no change. The error message remains the same. The computer will still not recognise the camera as a device an allow the photos to be downloaded from the camera.