My family recently switched to ATT&T and we got the 700 min. W/ unlimited messaging + unlimited calling to any mobiles. Whenever I try to open a picture message I get an error message that says "Retrieving failed Define network settings" and whenever I try sending a picture message, it would say "Set connection for sending MMS". I'm not sure whether it's the fact I didn't buy the internet plan or something is blocked. Can someone please help me? My cell phone is a Samsung Wave 533, which isn't provided by ATT&T.