How do I permanently delete email addresses from my MacBook Mail address book?
Macs Mail memorises email address that were used in the past. This helps mail to identify the mail address once user start typing it. However, it will also restore a mail address which may be entered incorrect by the user. Now this can cause trouble since it may send the mail to a wrong address.
To kill out these mail addresses, launch Mail app. Goto Window and select 'Previous Recipients'. This window will show up list of previous recipients with names & email addresses of people you have shoot the mail.
Click the Name, E-mail or Last Used bar at the top of the column to sort the list on your preferred criteria.
To remove someone from the Previous Recipients list so that Mail won’t try to auto-complete the address, click on the entry to select it and then click the Remove From List button in the bottom left corner of the window. You can select multiple entries at once by holding down the Mac’s Command key to highlight several addresses as you go. Click the Remove From List button to zap all the selected addresses at once.
If you find a contact that you’d like to officially add to the Mac’s Address Book program, select it and click the Add to Address Book button in the bottom right corner of the window.
Apple Mail is using 2 sets of contacts
1. Address book or Contacts.app
2. previous recipients
For the Address book (or in later versions called Contacts) open the application, then select the contacts you want to delete and press right-click > Delete card or on the top menu Edit > Delete card.
For the previous recipients open up Mail, then in the top menu select Window > Previous recipients. Select the 'contact' you want to remove and press the "Remove from list" button.
Now Apple Mail should no longer "know" (auto complete) the recipient.