I’ve seen a number of threads that touch on this, but nothing that coherently answers the question of how to resolve the problem. I am very happily getting and sending mail under my own identity/account, leaving the ‘Account’ property of both Send and Get blank. We have a shared mailbox, ‘Expenses…

Outlook send mail from shared mailbox reprise

loginerror (Maciej Kuźmicz) February 12, 2019, 2:00pm 9

I am not sure if relevant, but you could try going over this post:

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