I'm on a carrier unlock and I've tried the following: http://support.t-mobile.com/docs/DOC-4771 http://support.t-mobile.com/docs/DOC-2383 I installed the profile and proceeded to configure the settings as directed above. I restarted the iPhone and I still can't send MMS. I've tried both APNs listed. Before this I tried unlockit. ( http://www.unlockit.co.nz/unlockit/ ) There are two t-mobile options in the US listed on the site. I tried the first, reset the phone. No cigar. I tried the first, entered the network information detailed on the T-Mobile website, reset the phone. No cigar. I tried the second, reset the phone. Nothing. I tried the second, entered the network information detailed on the T-mobile website, reset the phone. Nothing. MMS messaging is enabled within my Settings. Please help, I am very annoyed. I have a factory unlocked iPhone 4 on iOS6 and I've searched through this forum already. I have tried all of the above with wifi disabled and wifi enabled. In the following photo wifi is enabled, but the symptoms remain the same with wifi on or off. The message appears to be sending but fails right before it finishes. Thank you.