I have a canon powershot. I have a canon powershot sd630. The camera works find but when I plug

Question

I have a canon powershot sd630. The camera works find but when I plug it in to my USB port on the computer (via the canon cable wire that came with the camera) the computer does not recognize the camera. I have been using this camera for two years and this is a new problem. Its as though the usb port on the camera is problematic. I am able to use the port on my computer's tower for other electronics without any problems.