I am unable to turn on wi-fi on iphone 4gs
Restart your iphone. Press and hold the power and the home botton for 15 seconds. The screen will turn black and appear with the silver apple logo. I hope that works!
If you cannot turn on WiFi or Bluetooth, you may well have a hardware problem. It may be time for you to make an appointment at your local Apple Store.
Best of luck.
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