This began around two weeks ago.. I've been unable to send any pictures via iMessage. It would show a red "not delivered" alert every time. Regular text is working fine. I updated to the newest iOS 7.1.1 today and still can't get pictures to send at all. On my iPhone 5, I've tried resetting all network settings and turned my phone on/off. This is also a problem on my Macbook Air, can't get pictures to send either. There'd be no red "not delivered" alert and appears to have sent successfully, only the recipient never receives the picture. Any one else experiencing this? Thanks!