More at http://support.apple.com/kb/ts3367
http://www.howardforums.com/showthread.php/1702150-Facetime-not-working-on-IPhone-4-using-straight-talk-service-also-visual-voicemail covers the other ideas.
Bob
I changed service carriers from AT&T to StraightTalk on iPhone 4S . Now FaceTime is not working. What gives.

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