Emails to Outlook, Hotmail etc bouncing back

Hi Daniel Goertzen,

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The error message indicates that the sending IP address has been blocked by Microsoft's email filtering system (S3140). This is a sender reputation issue related to the outbound mail server or network, rather than an issue with Outlook.com or the recipient mailbox.

To resolve this issue, we recommend:

• Reviewing the mail server to ensure it is not sending spam or unauthorized messages.
• Verifying that SPF, DKIM, DMARC, and reverse DNS (PTR) records are correctly configured.
• Submitting a delisting request through Microsoft's Sender Support portal: https://sender.office.com using the affected IP address.
• If possible, you may try switching to another network provider or IP address.

Please note that this is a community forum, and we do not have access to Microsoft's internal block lists, reputation systems, or the ability to remove IP addresses from those lists on your behalf. The delisting request must be submitted by the sender, mail administrator, or the organization that manages the sending IP address.

Once the reputation issue has been addressed and the delisting request has been processed, mail delivery to Outlook.com, Hotmail, and other Microsoft consumer mailboxes should resume normally.