[rottweiler]

I have an iPhone 4 with Tesco Mobile (O2) contract

Any message i send longer than about 4 lines seems to fail and the person receiving the message only receives about half of the message...

Any ideas ?

Network or phone fault ?

[davethorp]

What phone does the person you are sending the message to have? Sounds to me like their phone doesn't support joining longer SMS messages together. Normally when this happens they will still receive the message but over several SMS though from sound of your symptoms it sounds like not all parts of the long SMS are reaching them

If for some reason they don't receive all the sections of a message best suggestion would be to turn on character count in the messages settings and limit your messages to them to 160 characters

[rottweiler]

The messages are sent to various phones including other iPhones ???