I had that happen and it was a stumper. Drivers, OS, all OK and it turned out the router was set to EU and the desktop/laptop was set to US. Once I fixed the region setting the router showed up.
Now it is possible your adapter is in a dead spot and I always have to move it to the same room with nothing but air between for a test.
Bob
I have a two story house with my Netgear DGND3300 (ADSL Modem + Wireless N router combined into one unit) placed on the second floor in a central location. My office, on the first floor, is directly under the router (distance of about 15 feet). I recently purchased a Netgear WNA1100 USB dongle for my desktop in the office. Plus, I am using a Sony Google TV receiver in my family room (distance of about 25 feet from the router). I know my router is broadcasting the Wireless N SSID because I am using it to connect my Sony Google TV receiver however, my desktop only finds my Wireless G SSID. My security is set to WPA2-PSK. What am I doing wrong or how can I get my desktop to locate the wireless N signal (Win7 Ultimate)?

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