For the past three or four months, I have not been able to send MMS messages to non-iMessage users on my iPhone 4S. I have done the "data update" (calling ##873283#) and have done a full reset (Erase All Content Settings), and while those things will temporarily fix the problem (enough that I can send one MMS), the problem persists. I had an iPhone with AT&T before, and had absolutely zero problems with this. I know from browsing the forums and a general Google search that I'm not the only one with this issue. It seems as though there isn't a solid solution, however. Has anyone successfully fixed this problem? Is there something I'm missing? And yes, my MMS settings are turned on.
Sort of. I spent an hour on the phone with a Sprint tech last Friday. She basically had me do everything I'd already tried, and in addition, she blocked and unblocked text/SMS messaging from her end. After every step, she'd have me try to send an SMS, and each time it would fail. She finally asked me to do a full reset again. After the full reset, she had me test it for an hour, sending messages every few minutes. It seemed to be working. For the rest of Friday and well into Saturday, I was able to send SMS messages to non-iMessage users, but by Saturday evening, that was no longer the case. Now I can get one to go through about one out of every ten tries. Frustrating. I plan to call Sprint again, but I'll need to block off another hour of time.