Hi Ryan,
What changes have you made to Office or Mac before this error occur?
What's your account type? POP or IMAP?
Some email services require authentication for their SMTP server. Let’s turn on SMTP authentication for the POP or IMAP account:
- On the Tools menu, click Accounts.
- In the left pane of the Accounts box, select the account.
- Under Outgoing server, click More Options.
- On the pop-up menu, select the authentication type, and then enter your credentials as necessary.
If issue continues, test this in a new profile. Check the steps in
this article to create a new profile.
Any updates, please feel free to post back.
Regards,
Perry
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