False positive emails going to spam

Question

We are facing email delivery issues with our domain Stanfab.com when sending emails to recipients using Microsoft email services (e.g., Outlook, Office 365). Our emails are either being delivered to the spam folder or are not reaching the recipient's inbox at all.

In the message trace its showing domain reputation. I'm asking if domain reputation issue is there then all major email service providers like Google, Zoho, yahoo are mark as spam. In this case any other service providers are not marking as spam.

We have already configured SPF, DKIM, and DMARC, and all authentication checks are passing. Despite this, the issue persists. This issue is due to Microsoft’s AI filters assigning a Spam Confidence Level (SCL) of 9, which is causing our emails to be flagged as spam or quarantined. we raised 3 tickets via Microsoft 365 admin center 2510140030003810,2510160030002948,2510270030002731.

We first raised a ticket on October 14, 2025 (2510140030003810) but did not receive any proper response from Microsoft. As a result, we created a second ticket on October 16, 2025 (2510160030002948). Even after more than 10 days, the issue remained unresolved, with no clear update from support team.

Finally, we raised a new ticket on October 27, 2025 (2510270030002731) in the hope of getting the issue resolved. However, even after waiting for over 20 days, we have not received a proper solution or any meaningful update from support team.

Nobody is giving any update. One of other company domain starting with stan is also marking the same. What I can do? Any others have these type issue?

Answer 1

Hi,

As you have carried out most of the checks, have you tried submitting via the portal usually I had quick responses on this - In the Defender portal at https://security.microsoft.com, go to Actions & submissions > Submissions. Or, to go directly to the Submissions page, use https://security.microsoft.com/reportsubmission

Quick check can you verify the AnitSpam policies? - https://learn.microsoft.com/en-us/defender-office-365/anti-spam-policies-configure

The escalation is via Microsoft regional manager if you have contact via direct reseller or CSP?

Hope this helps.

JS

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