Hi @Peter Graham ,
Welcome to our forum!
It worked in the past but stopped receiving mail.
Have you done specific operations before that?
but the primary email which is also the user id for the Microsoft account hits an error.
Would you please provide a screenshot of it for our better research? (In order to avoid the privacy, please remember to hide your personal information.)
And what's the version of your Outlook for Mac? (Outlook>About Outlook) Please make sure you have upgraded your Outlook to the latest version.
According to your title, I noticed that you are concerned about how to add an account in Outlook for Mac, please refer to this article: Add an email account to Outlook.
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