Verify that your access point or wireless router is functioning correctly.
Check the Network name (SSID) of the wireless network and verify that the access point or wireless router is set to broadcast the Network name (SSID).
Change the channel on the access point or wireless router and click Refresh in the Wireless Networks tab.
If you still do not see the correct wireless network, you can click Add under the Preferred networks section and manually update the appropriate information to create the entry