Open your "Wireless Network Connection" where it displays the available wireless networks. Click "Change Advanced Settings". Now go to "Wireless Network Connection properties", and click the "Wireless Networks" tab. Click "Properties" then open the "Authentication" tab. UNCHECK the top box "Enable IEEE 802.1x authentication for this network".
This assumes you are NOT using any authentication at all. If you are, this will not fix your issue, but on most home wireless networks, you will not be using any authentication...