Wi-Fi Settings

• Your iPhone has settings to adjust your Wi-Fi access depending on your location and your connection abilities. For instance, when you're flying, you can set your iPhone to "Airplane Mode," which shuts down all of your connections. Check your settings to ensure that your Wi-Fi is on and ready to search for and detect a connection. Touch "Settings," and then "Wi-Fi" to see if any wireless connections are available. If your Wi-Fi is off, touch "Wi-Fi" and then "On."
  
  

Wi-Fi Range

• The typical Wi-Fi router has a range of 150 feet indoors and 300 feet outdoors, depending on various obstacles. If you're out of range of the Wi-Fi network, meaning you're too far from the wireless router, your iPhone will not be able to detect the connection. Find out where the router is for a particular Wi-Fi connection and see if you can move within range for better speed and a stronger signal.
  
  

Private Wi-Fi

• Wireless networks that are protected by a wired equivalent privacy, or WEP, key are not accessible unless you have the proper password. Although public Wi-Fi that is offered by businesses and establishments is free to use, other Wi-Fi may be a paid-service. Although your iPhone will be able to detect those Wi-Fi networks, you will not be able to access them without the correct password or key.
  
  

Network Settings

• After traveling, using your Wi-Fi in a variety of places or changing your network settings, you may find that your iPhone no longer detects Wi-Fi, even if it's a connection you've used before. This is likely due to a change in your network settings. Your network settings control how your iPhone interacts with Internet connections. By resetting the network settings, you restore your iPhone back its default settings so it recognizes Wi-Fi connections again. Touch "Settings," then choose "General. Scroll to the bottom and select "Reset" and then "Network Settings."