Hmmm ... is there any chance that your wireless device is disabled?
Control Panel -> Network Connections, you should see your wifi device listed. Is it enabled, disabled, connected,

Sometimes the wireless device comes with its own software that interferes with zero config. There's usually a setting somewhere that says "Let windows manage the device" or similar.
Hard to say what, but I can tell you from experience that wireless problems are never easy to solve, so don't give up!