AirPort base stations: How to find the Wi-Fi network when it doesn't appear normally
You may not be able to locate your Wi-Fi network from your computer. The Wi-Fi network may not appear in the Mac OS X AirPort Menu Extra.
There are several things that may cause these symptoms:
Wi-Fi from your Wi-Fi base station may be disabled (turned off).
Wi-Fi on the computer or device may be disabled.
Your computer or Wi-Fi device may be out of range of your Wi-Fi base station.
Your Wi-Fi network may be affected by radio interference.
Your Wi-Fi network administrator may have chosen to close (hidden) the network.
Try the following troubleshooting steps to restore the Wi-Fi network.
If only one computer is affected:
Check the settings on your computer and make sure Wi-Fi/AirPort is enabled.
Make sure your computer is in range of the AirPort base station (You can test this by moving the it closer to the AirPort base station).
If all computers and Wi-Fi devices are affected:
Make sure the Wi-Fi base station is plugged into a working electrical outlet.
Make sure your computers, Wi-Fi devices, and your Wi-Fi base station are not near any sources of potential interference, such as metal walls or microwave ovens.
Note: To learn more about potential sources of interference see AirPort and Bluetooth: Potential sources of interference for wireless devices and networks.
Make sure Wi-Fi is enabled on your Wi-Fi base station.
Note: To verify that your Wi-Fi base station Wi-Fi network is enabled, Open AirPort Utility and check the setting for Wireless Mode under the AirPort > Wireless tab. If it is set to Off, you may select either Create a wireless network or Extend a wireless network from the drop-down menu.
Make sure the Wi-Fi network isn't set to closed (hidden) on your Wi-Fi base station.
Note: To unhide your wireless network, Open AirPort Utility and uncheck Create a Closed network, located in AirPort > Wireless tab > Wireless Network Options...
Reset your Wi-Fi base station.
Note: To learn more about resetting your AirPort base station, see Resetting an AirPort Base Station or AirPort Time Capsule FAQ.