Cannot send/receive MMS and Network Mode cannot be changed

[#1]

I just received my Xperia U today and I was so excited to send screenshots to friends! Anyway, I've been able to send and receive regular sms texts but I cannot send and receive mms texts. I've researched as much information to resolve the issue and have tried multiple suggestions but nothing has worked! I've tried importing the data mms settings from my phone but it hasn't worked. My internet connection is fine but when I try to import the settings, it fails. I've also tried changing the APN settings but when I tried to send a mms, I kept receiving an error message saying it cannot send. I believe this MAY have something to do with my Network Mode preferences. I'm with AT&T and I know it is a GSM carrier. However on my phone, the Network Mode is set to "WCDMA (preferred)/GSM" and I've tried selecting "GSM Only" but it won't allow me to do so. Someone please help me!! 😕

[Johan]

If your phone software is branded to an operator this option might be disabled depending on how they have decided their firmware to work.

But I suggest that you contact your network operator to have them check MMS services for your SIM and also that you're using the correct APN settings.

[#3]

Thank you! I'll give them a call and update when I get more info.

[#4]

I called AT&T and they've informed me that my phone is able to make and receive phonecalls on their network but that my phone isn't compatible with their data network. On top of that, because it's a smartphone and AT&T recognizes it as such, I STILL have to pay for data even though I can't access it! Either I'll have to get another phone or I'll have to stick to WiFi and no MMS. I'm not really sure what to do now...

[teevee2486]

try this? i have the xperia u as well and this works fine for me.

i can use both the internet and MMS.

ATT

APN: wap.cingular

Proxy: wireless.cingular.com

Port: 80

Username:

Password:

Server:

MMSC: http://mmsc.cingular.com

MMS Proxy: wireless.cingular.com

MMS Port: 80

MCC: 310

MNC: 410

Authentication type:

APN type: mms