And it reads as if your cellular carrier needs to enable this for your plan or they need to tell you how to set it up.
Bob
My Samsung Galaxy S3 Mini (GT-18190N) won't send MMS messages, whenever I try I get 'message not sent, service not activated on network, server response error'. My network resent the CP message and when I check it in the menu it says installed. I tried installing again and switching the phone on and off but it still doesn't work. Is there anything else I can do such as remove specific apps or would resetting the device help? (which I would rather avoid) any help would be greatly appreciated, thank you!

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