iPhone 4 - unable to send MMS messages - O2 UK

[myuserid08]

I have an iPhone 4 on O2, for as long as I can remember I've been unable to send MMS messages.
I contacted O2 yesterday, who asked me to update the carrier settings - then send an MMS to myself (which failed).
They say its a hardware problem - apple want £130 to fix

 

[FlexPen76]

I used to have this problem. Check these settings are the same:

O2: If you can't connect to the internet using the O2 network on your iPhone, here's what you need to do.
Go to Settings/General/Network/Cellular Data Network or Mobile Data network and check that Cellular Data/Mobile Data APN, Visual Voicemail APN and MMS APN show as idata.o2.co.uk
Your Username should be vertigo and your Password is password
For picture messaging, you'll need to check -
MMSC = http://mmsc-ac.mms.o2.co.uk:10021/mmsc
MMSC Proxy = 82.132.254.1:8080
MMS Max Message Size = 2097152
If anything needs changing, just tap on it to edit, copy it in, and you're done. Any other fields aren't needed, so you can ignore them.
Alternatively, if you just want to connect to the internet and you've got a wifi connection, here's a link to download the settings instead - https://adc.o2.co.uk/apple_ota/83680261136B0006558626A21486/Iphone idata.mobileconfig

I think for mine it was the MMSC settings slightly different either the socket or the URL

Thats what fixed my issue.