My macbook pro 2011 fails to connect to my router wirelessly or even with an ethernet cable. It was working fine but has stopped. My iphone 4 does connect successfuly to the same router, and so does my PC. Also, if I connect my macbook to the internet through the iphone's hotspot and 3G services, it works just fine. What do I have to do to enable my macbook connet to my router.