We have discovered that using iMessaging can sometimes interfere with normal texting. Try disabling iMessaging in your settings to see if this helps.
Also, H2O MMS, or Picture messaging doesn’t work. Please see this faq for more info: http://www.thecellphoneguru.com/faqs/my-mmspicture-messaging-isnt-working-on-my-h2o-iphone/
Here are some trouble shooting steps for H2o:
- Go to “Settings”, tap on WiFi and temporarily turn it OFF
- Back in “Settings”, scroll down to “Messages” and tap to open it. Make sure MMS is OFF
- Go back to “Settings”, tap on “General” and then “Cellular”. Make sure “Enable 3G” is OFF & “Data Roaming” is ON.
- Scroll down & tap on “Cellular Data Network”
- Under “Cellular Data Network” put in the following:
- Cellular Data APN: att.mvno
- MMS APN: att.mvno
- MMSC: http://mmsc.cingular.com
- MMS Proxy: 126.96.36.199:80
- MMS Max Message Size: 1048576
- MMS UA Prof URL: http://www.apple.com/mms/uaprof.rdf
- Leave all other fields blank
- Click on the Home button to go back to the main phone screen
- Go back to “Settings” one more time, scroll down and tap on “Messages” and turn it ON
- Press the Home button and you’re set to send & receive MMS on H2o!
- Once you have set it up and tested to see it works, you can re-enable WiFi, turn off Data Roaming and turn on 3G (or leave it off if you’re not in a 3G area for AT&T devices on our network).