my outgoing emails are undeliverable saying its going as spam

Question

This message couldn't be delivered because the sending email address was not recognized as a valid sender. The most common reason for this error is that the email address is, or was, suspected of sending spam. Contact the organization's email admin for help and give them this error message

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Moved from Microsoft 365 and Office | Microsoft 365 Defender | Other | Other

Answer 1

If your outgoing emails are being marked as undeliverable and you receive a message indicating that the sending email address is not recognized as a valid sender, it is likely due to the email address being suspected of sending spam. This situation can occur if the account has been flagged for spam activity, which can restrict its ability to send emails.

To resolve this issue, you should contact your organization's email administrator for assistance. They can investigate the account's status and take necessary actions to restore its sending capabilities. Additionally, they may need to check if the account is listed on any spam blacklists or if there are any other restrictions in place.

For further details, you can refer to the information regarding compromised accounts and how to regain control of them.

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References:

• Remove blocked users from the Restricted entities page
• Email non-delivery reports and SMTP errors in Exchange Online