I have two Samsung Galaxy Centura phones running Android 4.0.4. I am unable to send MMS messages with either phone. I have found plenty of references to set up APN settings to I can achieve this, yet for some reason, my phones do not even show APN settings. When I go to "wireless & networks", then to "mobile networks", I only have a "data enabled" check box. It is my understanding this is where I am supposed to be able to enter APN settings. I find it very frustrating that I do not have sufficient access yet to respond to the private messages I have received from techs offering help. This "help" system makes no sense to me and I find it frustrating to navigate.