My.Support – Changing your eMail Password in Apple Mail
Changing your email password in Apple Mail
Problem: How do I change my email password
Change your email password in the Mail Preferences for both incoming and outgoing mail.
Instructions: This article details how to make the outgoing server changes to your Apple Mail account. (1)
Click on Mail and then select preferences from the drop down
Enter your new password in to the password field on the right.
Select edit SMTP server list from the drop down menu.
Select the outgoing mail server which is associated with your email account
Click on the Advanced Tab and update your password.
Click on OK.
Then close the accounts window.
If prompted save any changes.