I'd start with the installing the drivers from the disc that came with the mobo. If that doesn't help, check to see that LAN/WAN isn't disabled in the BIOS. You could also use a computer that has a network connection to download the latest drivers, or check the mobo manufacturer's website to see if there is a BIOS update that addresses this concern. As a last resort, you can contact the mobo tech support for possible RMA.