To remove an address from the auto-complete list do this. Start typing the recipient's address or name in a new message. Select the desired address from the auto-complete list as if you'd compose an email to them. Once you select it click in the message body and you will see the address turn blue. If you will then place your cursor at the very right end of the address next to the right facing arrow you will see a down arrow appear. Click that down arrow and from the drop down box click “Remove from Previous Recipients List" from the menu. Next time you start typing a name is will not appear.