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Questions tagged [dmarc]

Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a mechanism by which the owner of a domain uses specially formed DNS records to express domain-level policies and preferences for email validation, disposition, and reporting.

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Does this report mean someone is attempting to send emails fraudulently or that I have things configured wrong?

Pretty new to spf/dkim and dmark. After setting this up just this morning I already got a report on a new website. Our service eamils our users via sendgrid and the rest of the emails are sent from our google workspace accounts. Our SPF looks like…
John
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DMARC failure for delivery report

I have a Docker-based mail server (Mailu) setup. It's working great except for delivery reports which are sent automatically (one of the user mailboxes is full and a "Quota exceeded" notification is sent to the sender). The reports are rejected by…
andi
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Turn off DMARC report for pass

I would like to receive reports only for DMARC quarantined mail and failures, but I still receive mails for every successful e-mail that has been sent from my server. Configuration in dns looks like this v=DMARC1; p=quarantine;…
Hynek Bernard
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SPF and DMARC - how is the SPF policy used

My domain has a strict DMARC policy (p=reject) and a standard SPF policy with ~all catchall. My email provider is Google Workspace. I received an email spoofing my sender address. It came from 41.174.75.34 - a Zambian IP address which is blacklisted…
chutz
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Can somone explain this DMARC report? did it fail or pass? why am i getting these if they passed?

Can anyone tell me what this means? As far as I can tell they all pass, but I dont know if this is yahoo sending me this or my server telling this passed or what. My server I set up DMARC I think …
user603315
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Forward messages to Gmail (postfix+SRS) has DMARC failure even though SPF and DKIM succeed

I run my own domain, but forward many email addresses to my gmail account. Recently, I started seeing a lot of messages marked by gmail as spam. I have SPF set for my outgoing email, and use SRS to rewrite the from address as my own. I also have…
Mikeage
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Windows DNS and long DKIM keys

One of our third party services that we sends as provided us with a DKIM record that is longer than 255 characters and they won't provide a shorter one. How do I properly use what they've provided with Windows DNS? I've tried the following solutions…
kausner
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Email forwarding SPF and DKIM domains

In preparation for publishing a strict DMARC policy, I've: Published a reporting-only policy. Gathered nearly 2 months' worth of reports and uploaded them to dmarcian. Started analysing them and looking for usage problems which need to be…
mythofechelon
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Google DMARC Support, DKIM and SPF fail

This morning I received my second email from noreply-dmarc-support and I really don’t understand why. I have tried looking it up and I have seen through forums here that it has to do with emails, but I haven’t sent anything. Would this mean someone…
Celeste Gonzalez
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Why is opendmarc SPF failing this arriving message?

Why is this incoming message failing? postfix/smtpd[4776]: connect from mail-mw2nam10on2073.outbound.protection.outlook.com[40.107.94.73] postfix/smtpd[4776]: Anonymous TLS connection established from…
Andrew
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Postfix send mail only to GMail, all other domains are deferred and not sended

My Postfix server is running on Debian Stretch. It is able to send emails to a GMail address without problems which are not considered as spam. At the DNS level I configured DKIM, SPF and DMARC and GMail informs me of the "Pass" value for all three.…
Zetam
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How to resolve "signing key too small" issue from mail-tester

We've recently been having some email delivery issues, so I find myself taking my first dive into the email server set-up world to make sure our emails are arriving as expected. I ran mail-tester a few days back and it told me to add this DMARC…
Vincent
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Using SPF and DMARC records to combat invalid email subdomains

I have been able to confirm that bad actors are sending emails from nonexistent subdomains of my company's primary domain. Let's say my primary domain is foo.com. Email is sent from that base domain from my own mail system. Due to partnerships…
CaptainZack
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Can I set dmarc to tell receiver to fail if no DKIM signature provided in email?

I set SPF, DKIM and DMARC for my email server. I build my own mail server on my personal computer. Then I disable signing DKIM signature and send an email to Gmail. Gmail shows SPF pass and DMARC pass and tell me it's a normal/good email. So my…
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How do I whitelist another sender (e.g. Sendgrid) for DMARC?

We host our own e-mail but use Sendgrid to send mail on behalf of a few internal PHP services that can't easily handle our mail configuration (e.g. they disallow self-signed certs by default, so getting them to connect to our server to send out…
Will Matheson
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