Just got the new AirPort Extreme 802.11ac and thought I would also configure the Guest Network. I've discovered that all my Apple devices will connect, except my iPad 3 which always returns an invalid password error. I've tried configuring other passwords for the network but get the same issue. Connecting to the Primary network is fine. My wife's iPad 2 connects with no problem to the Guest Network. I didn't try this with the old AirPort Extreme.
Is anyone else experiencing a similar problem? I don't plan to use the Guest Network with my iPad 3 but visitors may have the same issue.
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