iPhone 5 running iOS 6. Worked perfectly up until today. Now it can see wireless networks, but gives an error message (screenshot below) when I try to connect. I can see the networks, but the phone won't connect. Tried turning wireless on and off, the phone on and off to no avail. I've tried with two different routers, same result, and both routers work fine with other Macs, PCs, an iPad 2 running iOS 6, and an iPhone 4S running iOS 5.1.1. Any help?