Every wifi unit that ships out has been thoroughly tested to make sure it is working properly.
If you cannot see the window light appear on your wifi network, the wifi unit in the light probably needs to be reset.
To do this, unplug the window for a minute. Then plug the window in for a second, and then unplug it for a second. Repeat until the light starts flashing. That tells you that you have reset the wifi controller, and you should be able to pair it again.
Also, you have to make sure you are connecting to a 2.4Ghz network, not 5.0Ghz
This should take care of the problem, but if it doesn't, please contact us and we'll do some other troubleshooting.