Found a solution. – Guitar Hero Live Companion Review

Well, reviews here complain about this app. One other guy claimed there was a solution, but that didn't work for me. The app is absolutely great, it's just that hooking it up is a pain in the butt. Fortunately, I found a solution that's pretty simple. Start it up w/o WiFi, go through all your steps until you reach the code entry screen. Then turn on the WiFi network your console is hooked up to and voilà! Your thingie should be workin' just fine! If not, that's another problem you have. Good luck! P.S.: C'mon, devs.
Review by NoiseMaelstrom on Guitar Hero Live Companion.