My Wi-Fi will not turn on in settings on my IPhone 4S, its just greyed out. I have >reset Network Settings and I have performed a Software Restore twice through ITunes, But still My Wi-Fi is greyed out.

My Wi-Fi will not turn on, on my IPhone 4S. It's just greyed out in settings. I've performed an update to IOS 6.3, two software re-sets through ITunes and a Wi-Fi reset through the phone settings, but the problem still persists.

I was informed by my phone provider (O2) that rhere was a "known" problem with Apple concerning the latest IOS 6.3 operating system and lack of compatability the IPhone 4S.