got a at&t Nokia lumia 520 for Christmas and one of the new at&t 4g sims card from straight talk to upgrade from my old iphone 3g and i cannot send or recieve mms ( picture messages) , regular cellaur service works for calls, i can send and receive regular text messages, internet data works fine. but when i try to send a picture ot someone it waits a few minutes then says unable to send message, and on receive i get the message about downloading the picture and when you click it it just refreshes the message and does not even try to download no matter how many times you click it. i have tried the generic Nokia setting on straight talks site and have tried the old settings also like the iPhone had but not of them work at all only the newest setting gets something to try and download but does nothing after that even when clicked.
the current apn settings are
mms
APN: tfdata
user name STRAIGHT_TALK
password
WAP gateway (URL): mms3.tracfone.com
WAP gateway port: 80
MMSC (URL): http://mms-tf.net/
MMSC port: 80
thanks for the help