Wi-fi greyed out permanently so unable to select ..please help

I have the same problem. Everything was fine in my 4s until 6.1.3 update. Then the wifi and bluetooth stopped working. Apple has to fix this with a new update. There are hundreds of 4s holders with the same problem. This is unacceptable.

For me and some other people it worked to take the sim out and restart without the sim. Then the wifi worked and put the sim in without switching the phone off. It is worth a try