1. Make sure there is an appropriate SIM or micro-SIM installed in your iPhone or iPad, that you have a working Internet connection on your computer, and that iTunes 9.1 or later installed on your computer.
  2. Connect the device to your computer and open iTunes.
  3. If a carrier setting update is available iTunes displays a prompt: Click here to enlarge
  4. Click "Update Settings" to load the confirmation dialog. Click here to enlarge
  5. Click OK to dismiss the confirmation dialog.
  6. Restart your device:
    1. Hold the power button until "slide to power off" appears.
    2. Slide to power off your device.
    3. When it is off, press the power button to turn it back on.
Additional Information




The carrier update files are stored in the following locations.
  • In Mac OS X:
/Users/[Username]/Library/iTunes/iPhone Carrier Support/
  • In Windows XP:
C:\Documents and Settings\[Username]\Application Data\Apple Computer\iTunes\iPhone Carrier Support
  • In Windows Vista:
C:\Documents and Settings\[username]\AppData\Roaming\Apple Computer\iTunes\iPhone Carrier Support\ in Windows Vista.

The version of the carrier settings is visible on iPhone and iPad Wi-Fi + 3G by tapping Settings > General > About and looking next to "Carrier". If you restore with a new version of the software, the carrier settings update may be included with that update. If not, iTunes will indicate that a carrier update is available after the restore.

Locating iPhone wireless carriers
http://www.guarforum.net/info/IphoneWirlessCarrier/index.htm