My macmail indicates server not supporting xapop authentication. All the settings are per your instructions and I get a yellow caution icon with that message.
Hello, and thanks for your question.
Our servers do not support Authenticated Post Office Protocol (APOP) like your Mac Mail client says. APOP is an older and less used protocol compared to IMAP, or POP3 over SSL.
You can simply be sure that you're using email over SSL and this will encrypt your email username and password to the server much like the older APOP protocol would.
You should be able to switch Mac Mail over to using the standard POP3 protocol by following these steps:
Click Mail, then click Preferences
Click on the Accounts tab
Select your email account having the authentication error
Click on the Advanced tab
From the Authentication drop-down, select Password
Save your account changes
Close, and then re-open MacMail
Please let us know if you're still having any issues at all.
- Jacob