I had the same problem a few years ago. When I called customer support, they had me power down the machine and plug in a different mouse that I had lying around. My first thought was,
YOU HAVE GOT TO BE KIDDING ME!
But it worked. As weird as it sounds, I would at least try a different mouse and keyboard, it's a simple test. Make sure you power it down, apparently someone did not on the machine I was working on.