When you atempt to connect to a Wi-Fi router that requires a WEP password by using the correct password, you may not be able to connect to the Internet or other Wi-Fi devices on the same network. You may note that the AirPort Menu Extra shows an AirPort icon with an exclamation point and that your computer has a self-assigned link local address (such as 169.254.x.x). The AirPort menu may also indicate that there is an "Alert: No Internet connection..."
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