Deliverability issue: Valid transactional emails being dropped/quarantined

Question

Hello Microsoft Deliverability Team,

We are the administrators of the domain [Moderator note: personal info removed]. We recently set up Amazon SES to send highly anticipated, transactional verification/signup emails for our software application.

Our emails are completely failing to reach Microsoft/Office 365 users. They are not landing in the Inbox or the Junk folder, indicating they are being silently dropped or quarantined by EOP.

Please note the following:

We are 100% authenticated. Our SPF, DKIM, and DMARC (p=quarantine) policies are strictly aligned and passing.

This is purely transactional traffic (user-requested signup links), NOT marketing or bulk mail.

We have verified our setup using external tools, scoring a perfect 10/10 on deliverability metrics.

Because this is a newly active domain, we believe we are being hit by a false positive in your new-domain reputation filters. Could you please review our domain/IP reputation and mitigate this block so our customers can receive their signup links?

Thank you.

Answer 1

Please note that our forum is a public platform, and we will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data. 

Hi @Jayagopal Narayanaswamy

Thank you for posting your question in the Microsoft Q&A forum.  

First, I would like to clarify that this is a user‑to‑user support forum. Moderators, community contributors, and external Microsoft participants here do not have access to backend systems and cannot directly intervene in Microsoft service behavior. Our role is limited to providing technical guidance and best‑practice recommendations based on the issues and scenarios shared by users. 

I understand that your current domain (managed and hosted through Amazon SES) is experiencing deliverability failures when sending email to Microsoft/Office 365 users. Since your configuration is fully authenticated, with SPF, DKIM, and DMARC (p=quarantine) correctly aligned and passing. 

At this point, I would recommend asking your affected recipients to contact their Microsoft 365 administrator. Their admin can review the message traces, validate your sending domain, and mark it as a trusted sender so your messages can bypass filtering policies on their side. 

Additionally, you could consider contacting your email service provider to further investigate any reputation‑related issues and ensure your domain/IP is not being mistakenly filtered. 

Apologies for redirecting you to the related support team. As community moderators do not have the ability to review backend filtering results, contacting the appropriate admin or provider support team will give you the fastest and most accurate assistance. 

Please feel free to correct me if I misunderstood your request. If you have any additional concerns, feel free to comment below. I would be more than happy to assist. 

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Answer 2

To address the deliverability issues you're experiencing with your transactional emails sent via Amazon SES to Microsoft 365 users, consider the following points:

1. New Domain Reputation: Since your domain livewirecad.ai is newly active, it may not yet have an established reputation in Microsoft's systems. New domains often face stricter scrutiny, which can lead to emails being dropped or quarantined due to perceived risks.
2. Email Authentication: While you mentioned that your SPF, DKIM, and DMARC policies are correctly configured and passing, ensure that the DMARC policy is set to p=quarantine as you indicated. This means that emails failing DMARC checks will be quarantined, which could impact legitimate emails if any misconfigurations occur.
3. Monitoring and Feedback: Utilize tools to monitor your domain's reputation and email deliverability. This can help you identify if your emails are being flagged incorrectly. You can also consider setting up DMARC reporting to gain insights into how your emails are being treated by recipient servers.
4. Requesting Delisting: If you believe your domain or IP has been mistakenly added to a blocked senders list, you can use the Office 365 Anti-Spam IP Delist Portal to request removal. This can help mitigate the issue if your emails are being blocked due to reputation filters.
5. Contacting Support: If the issue persists, consider reaching out to Microsoft support directly for further assistance. Provide them with details about your email setup and the issues you're facing to facilitate a review of your domain's reputation.

By following these steps, you can improve the chances of your transactional emails reaching Microsoft 365 users successfully.

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References:

• External senders - Troubleshoot email sent to Microsoft 365
• How to avoid email authentication failures when sending mail to Microsoft 365