PC can't recognize modem

Hi, I'm feeling helpless. I can't connect to the internet on my desktop pc after I reinstalled windows. I have linksys wrt320n router and I can connect to it only by wi-fi. When I try to install router's setup wizard or network magic - it writes that my computer is not connected to router though it is connected in the same way as it was before. In the LOCAL AREA CONNECTION it is also written...