Why won't my iphone send pic messages?

I have an at&t iphone 4 on pay as you go, it worked perfect all the way up to 5.1.1 software then when i updated to the 6.0 and so on it will not let me send or receive pics. What can i do to fix this problem?

You will need to check your network settings and MMS settings to ensure both are set correctly. If you are unsure, ask your network provider to send the settings to your phone. The settings may arrive in the form of a message, which should be opened, stored and not deleted. You should also check the plan you are on to ensure that you can send data messages and multimedia messages. Again you may need to check with your network provider. If you want to send your pictures by email, you should check that your email settings are also configured correctly on your handset.

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