I ran into this problem last night when i upgraded to the newest itunes 11.1.4.
I have the iphone 4s. after thinking it was the iphone i just recieved, because as everyone with the 4s has come to relize when you update to the new 7 os it grays out the wifi, which then you cannot connect to any wifi.
Just for another info update, they say its the phone, but if your fortunate enough to have a back up in itunes, you CAN erase the iphone and regain the ability to reconnect to wifi. problem is when your phone wants to activate, at least with my Verizon service , it makes you update to the newer version and guess what... wifi will not work again (greyed out)
Back to what i was explaining about last night. I plugged my iphone to my computer, as i always do, and the itunes reconized and open the app. At that point i got the pop up window that advised of an update and so i said ok and updated to the newer version of itunes. After update it tells you that you have to restart your computer.
Now here is where your problems will begin! Again i thought it was the dang iphone messing up again. I spent hours trying to get itunes to reconize my iphone. No Luck. I started out trying to reset the networks,and eventually reset the whole iphone to factory conditions.
To make a long story short, i about gave up, then i thought. let me try one more thing, I went into system restore and restored my computer to a week earlier, which also reinstalled the older version of itunes....guess what? IT RECONIZED MY PHONE AGAIN! Just to test my theory, i opened up itunes and let it update the software again...well you can just guess what happened right? it did not reconize my iphone again.
So word to the wise, dont update itunes if you have the 4s...but if you updated itunes and it does not reconize your iphone 4s, and you have the ability to restore your computer to an earlier version, (dont forget to back up your data just in case), that will re-enable the communication and keep you from the hours of frustration trying to figure out what went wrong.
Apple is really commiting suicide in my opinion, i really like the iphone, but lately its like the three stooges are back there running the show!