When you open certain emails on your iPhone, the email is not complete, instead you get this message in the body of the email “This message has not been downloaded from the server.” This is a problem with the default email application that comes with the phone when it doesn’t understand the header of the email and it cannot download the rest of the message.
Some of this solutions may not apply to you depending the type of email setup you have on your phone. Please contact your IT Consultant for more help. Try these steps and see if the problem is fixed.
Restart your iOS Device
Note: Must of the problems get resolved by restarting your device and let the application re-try.
Reset your network settings:
Change the way the phone communicates with the server.
Note: This steps are only if you are using POP connection
If none of the steps above works you may want to try an alternative and better email app for your phone than the default one.