BT kindly migrated my Broadband to the MS Office 365 Server earlier this month so I had the lovely task of changing the emails settings on all of our household devices. Windows 7 laptops no problem, Apple iPad no problem, then came the turn of the iPhone and Apple Mac. All seemed to go well and new emails were being received ok. Then when we tried to send emails from these two devices we hit the same problem. Both failed to send the emails. I rechecked the settings, compared them to the iPad and even tried setting them up from scratch again. No joy the emails still won't send.
So what do I do now, any ideas on why the Apple Mac and iPhone should have a problem and the iPad not? I would add that all devices were using the wifi.
Double check the security settings on the outbound server - my guess is that it is set to use authentication (which it should) but is probably using 'Same settings as my incoming server' or the equivalent on the iPhone. You need to use the *complete* email address, not just the part before the @ sign, which a lot of clients seem to use.
Double check your settings against the settings in this article, that should get you up and running.
Adrian
have you tried an email app? something like altamail? might be a lasr resort?