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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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Is email deliverability impossible with a .name email address?

I have a dot name domain. .name is an odd TLD: they originally only offered third level domains, eg first.last.name, so that more people could get their own name. They also included the first@last.name email address with each domain registration.…
ryan
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DMARC strict vs relaxed alignment?

I've been configuring DNS records for a mail server and got stuck when it came to DMARC's alignments. I know that both relaxed and strict are valid options, as well as relaxed being default setting. However, I am wondering if there is a commonly…
user305491
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DMARC failing on Mailgun when forwarding occurs

We recently increased to a quarantine policy and are thinking of going to reject - but we stumbled across an issue we can't seem to identify a root cause for. Specifically, forwarded e-mails appear to be having issues and we can't figure out why. We…
Eli
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How to recover domain name from previous bad SPF record?

TL;DR: We had SPF too permissive (+all) and spammers used this to send tons of spam "from" our domain. We restricted that to ~all and added DMARC (not DKIM though), now other providers do not trust our real emails. How to make them trust our…
Alexey Kamenskiy
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Improve Spam Confidence Level (SCL) for outgoing emails

I have a postfix SMTP server on Ubuntu. I have valid SPF and DKIM records, as verified by the email header my customer received. Authentication-Results: spf=pass (sender IP is XXX.XXX.XXX.XXX) smtp.mailfrom=mydomain.com; hotmail.com; dkim=pass…
Raptor
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correct order for Postfix milters

I use the following milters with Postfix: ClamAV, OpenDKIM, OpenDMARC, Rspamd This is also the order they are being called via smtpd_milters. What would be the best order for them regarding performance, resources and spam protection?
basbebe
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How can you tell the difference between rua and ruf DMARC reports?

I have a client that's receiving DMARC reports from various providers however the reports indicate that all checks 'PASS' and all DMARC/DKIM/SPF checking tools indicate the DMARC records are fine. The reports are in XML format and zipped up. Is…
user315851
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Only enable SRS when forwarding to enable DMARC

I am setting up a mail server on my VPS and in order to prevent spam and being marked as spam I have enabled SPF, DKIM and DMARC. However, I do not want to host my own mailbox, so I forward the incoming mail to external mail accounts, e.g. Gmail.…
Matthijs Steen
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DMARC is blocking email that seems like it should be allowed

This is the DMARC record we have set v=DMARC1; p=reject; rua=mailto:[redacted]@coinbase.com; adkim=r; aspf=s So we are rejecting any not match with SPF strictly, and DKIM is relaxed. Here is the SPF record: v=spf1 mx ptr include:_spf.google.com…
Brian Armstrong
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How to prevent emails from my domain through mailing lists to be rejected due to DMARC

I operate my own mail server at speedofsoundgaming.com and mwtd.net. I recently added a DMARC record to my domain to help prevent spam, and once seeing that things seemed to be working, upped the level to quarantine from none. However, I had not…
Michael Taboada
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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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DMARC fail, but DKIM and SPF are passing

I am using AWS SES (in sandbox mode) to send an email to a GMail address. Unfortunately it gets flagged as spam. Google is nice enough to tell me in the message details that it is a DMARC failure I read the official documentation :…
YannP
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Using DMARC techniques to block Backscatter

We run a small email (receiving not bulk sending) service (~ 300 domains or so) for our customers and are just starting to introduce DMARC. One of the reasons for doing so is to help stop backscatter (NDRs for emails that weren't sent) by helping…
Rob Lambden
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Why use DMARC when SPF -all can do the job?

With DMARC I can set the policy to rejct mail. But isn’t it the same I can do with -all from within a SPF? Same goes for quarantine and a softfail ~all. Beside the reporting where is the benefit using DMARC on top of SPF?
Gordo2019
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SPF and DKIM pass, but DMARC fails for source_ip

I have configured our DMARC policy to quarantine and our domain SPF and DKIM are configured appropriately. The SPF record is as follows: v=spf1 +a +mx +include:sendgrid.net -all However this is the report being returned: …
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