I have a desktop PC using Windows 7 Pro. and a Airlink N 150 Mini USB wireless adapter. My 2Wire modem/router from AT&T was failing to stay connected and was replaced today with a Netgear 7550 modem/router from AT&T. I installed the Netgear 7550 and am able to access the internet with my Asus Laptop, my LG Thrill phone, and my Samsung Galaxy 2 tablet with no problems. However, my Desktop cannot connect to the internet and the Window Network diagnostics returned the following message: Network Connection doesn't have a valid IP configuration. How do I go about connecting my desktop to the Netgear modem/router so that I have access to the internet? By the way I am able to connect to the internet using an ethernet cable and a LAN connection.
The system is stuck back in the days of the old router. Go into Control Panel>Network and Sharing Centre and click on Manage Wireless Networks in the left hand pane. Find the old network in the list and click Remove then find the new SSID or network name and click to Connect or set it up manually with the information you used on your other devices.