Mac OS X Mail: "The server rejected the password" alert, even with correct password

Mail might tell you this, even when you're using the correct password:

"The server {server name} rejected the password for user {username}. Please re-enter your password, or cancel."
This message may appear several times while trying a correct password.

This can happen if the mail server is not available for authentication or cannot be contacted. Click Cancel, then wait a few minutes. After waiting, choose Go Online from the Mailbox menu, then enter the same password.

If this doesn't help, you may indeed be using the wrong password, or it may have been changed. Check with your Internet service provider about how you can reset it, if necessary.
Published Date: Oct 7, 2016