I cannot Send an email. I get error msg:"SMTP server doesn't support authentication." How do I fix?

I’m a new user. I cannot Send an email. Whenever I try, I get an error message: “SMTP server doesn’t support authentication.”  The unsent email stays in the Outbox. I cannot find this error message in any of the documentation, and would greatly appreciate knowing what’s wrong.   Thank you!

Check that you have the correct server settings, as provided by your email provider, in your account setup.

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