1) Go Setting 

2)Select Mail,Contacts,Calendars

3)Add Account

4) Select Other

5) Enter "your name", "your email address" & "password", and click "Next"

 6)Key in "mail.YourDomain.com" for host name

  and key in your "domain email" and "password" for username and password,then Click "Next"

7) Follow below setting, all the mail server host name use "mail.Yourdomain.com", and also turn "Use SSL" off.