I'm trying to send my wife texts via Messages from my MBA to her iPhone on iOS5. Up until last night, all the messages have been sent fine, but since then, the Message sends and the Delivered message pops up. But within seconds, the Delivered message disappears and the red "!" appears. I try to resend but the same thing happens. I tried closing out of Messages and restarting my Mac but it didn't help. Edit: the issue is resolved. I closed out of all my conversations, Signed Out of Messages and quit the app. Then, I relaunched Messages and Signed In. I tried to send a couple for texts to my wife and she received them.