I have been charged for 7 instances within messages for supposedly sending a picture, which I never do as I know I will get charged as this is not covered within my contract. So the question is why ?
Auto conversion, adding a subject line or sending to an email address.
Go into settings and turn MMS off which will stop MMS function completely on your phone.
If you read the previous threads about this,you will probably find the answer.
Most phones will warn you they are converting the sms to mms, but if u have an iphone they don't.
One of the most common scenarios with iphones is if the message is longer than 160 characters it converts to mms instead of spliting it into several sms. Hope you have found your answer
@Anonymous If my memory serves me right there is another feature on some phones (or maybe it is a feature of some keyboards) whereby if you select to insert a Smiley (emoticon, or whatever they are called) it automatically converts a text sms into a picture mms.