I just recently for Comcast and I have their Arris gateway. A laptop, desktop, 2 iPads, and my wife's 4s connect to it fine but for some reason my 4 can't. I get the wifi symbol but when I try to do anything nothing loads and after waiting a while I get a screen that says safari can't connect.i have tried changing the security settings as well as the channel. I tried forgetting the network and turning wifi on and off. I just recently tried restoring my iPhone as new. Nothing works. I can't seem to find anything other than those options to try and fix it. Thanks for the help.