I recently spent a good chunk of a day troubleshooting the problem "when certain people message my account on Apple Mail, I get the message twice." Confirmed t

I recently spent a good chunk of a day troubleshooting the problem "when certain people message my account on Apple Mail, I get the message twice." Confirmed that it wasn't user error, and was common, never made got another inch of headway. My eventual diagnosis was "at least you're getting the message!"