Using New Outlook on Windows for professional communication and productivity
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Technical details
SmtpSubmissionPermanent5XXException: Smtp submission failed. Server 'mail.b.hostedemail.com' Port '465'. --> Unexpected SMTP server response. Expected: 250, actual: 550, whole response: 550 5.7.1 Message detected as spam. [1714366816-457409].
Failure code: 21f5