IPhone - the sender address was rejected by the server

if you have getting this error, you may do following step to solve the issue.

• (Optional) Delete the Account in the Settings Section
• Add new Account and add required fields
• Advanced -> Incoming Settings -> Server Port: 110
• Outgoing Mail Server -> Server Port: 587
• SSL off
• Double click the apple button, close the mail application to be able to effect the settings that you did
• Reopen the mail application

That's it