My AT&T Wireless devices find FR but not when using TimeWarnerCable REGARDLESS of OS.
I just did it with same setup you have. Go to your wifi and after your network name click the little i for info on an apple device, or whatever info link there might be on a non apple device. Then you can change the dns numbers.
I had Verizon, it changed to Frontier I went on line typed in search engine open DNS iPad OMG very simple step by step with pictures!!! I was up and running again!!! My android phone is a bit trickier I will work on that later !!!!