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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Should smtp_helo_name always be the same as your MX record?
I can't seem to satisfy HELO checks on SPF records in all cases. I have an SPF record for my domain like this:
"v=spf1 mx -all"
The MX records in the zone are:
mx0.mydomain.org.uk. ...
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openarc: can't parse Authentication-Results
I've just set up openarc on fedora38 with postfix-3.7.9. I believe it's working properly, but I have a few questions.
I'm seeing messages like this periodically. I've found another similar report from ...
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DMARC Authentication in SendGrid is expecting a different value from the current one
I have one SendGrid account [email protected], I have been using it to send transactional emails from [email protected]. When I check the account [email protected], I realized that ...
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how to add multiple DMARC entries?
I use several different services to send out emails from my domain. I already have a CNAME record for _dmarc.mydomain.com that's set to mydomain.com.dmarc.emldlv.net for one service, however, another ...
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Trying to figure out a DMARC/DKIM situation
I recently helped a friend implement DMARC/DKIM/SPF and got a report that makes no sense to me.
Their domain is hosted on SquareSpace, they use Google Apps for email, and Mailchimp for mailing lists. ...
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Understanding DMARC report - DKIM pass on SPF fail
I am looking for some help understanding a DMARC report for my email server. The xml content looks like the following:
<?xml version="1.0" encoding="UTF-8" ?>
<feedback>...
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"Undelivered Mail Returned to Sender: DMARC check failed" from forwarded mails
I'm using Procmail to forward mails to another server.
I'm often getting an error message from the recipient server:
host smtp-in.orange.fr[80.12.26.32] said: 501 5.2.0
y8XgrepnBNXb2 Mail rejete. ...
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What are these DMARC failures about?
I've been toying with dmarc off and on for the last couple of months. Currently I have no policy set. I am using URIReports for report collection and analysis. Most of the results are good. We use ...
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DMARC, SPF and DNS wildcards
My domain configuration has one domain and three subdomains, one of which is identical to the mail server's hostname:
example.com
sales.example.com
internal.example.com
mail.example.com
I initially ...
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How to get SPF alignment to pass DMARC for a subdomain?
I have the following DNS configuration:
$ dig +noall +answer -t txt example.com
example.com. 626 IN TXT "v=spf1 +a +mx include:sendgrid.net include:_spf.google.com -all"
$ dig +noall +...
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AWS-SES sending from one site, from is another site - will DMARC help or hurt
Alright, to keep this simple:
I have a project that is using AWS's SES to send transactional emails. The project is hosted on one site (let's call it example-site.com), but for reasons, the From: is ...
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This relay isn't allowed to send mail "From" gmail.com
I'm on GoDaddy and since about January 2024, I've been getting this message from various gmail and yahoo accounts: ECDHE-RSA-AES256-GCM-SHA384:256 CV=yes: SMTP error from remote mail server after end ...
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SPF failing even though source IP is in the SPF record
I've seen (and think I understand) when DMARC checks fail on SPF because, e.g. the email has been forwarded and such like. But I don't think this is the case here. All checks on sites like MXtoolbox ...
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Phishing email but with SPF, DKIM and DMARC in "PASS" status
I received an email from a company that looked fine. Gmail deemed it ok. I checked the domain and the various DMARC, DKIM and SPF headers: they are all in "PASS" status. The sender's IP also ...
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SPF spf.protection.outlook.com is invalid for messages within tenant
When sending mails through our Exchange 365 service those mails get through successfully, but if we look at the mail headers we see that where the sender and recipient are in our tenant the mail's ...
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O365/Exchange: Send From: external domain using connector and transport rule?
I have a successful and working 365 install (it's just family, but we're an Enterprise tenant because we have multiple domains.) Everything is working fine and I've recently been reviewing and ...
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Is it a good idea to add `calendar-server.bounces.google.com` to my SPF record?
I'm trying to maximize my company's email deliverability and DMARC reports tell me we are failing DMARC SPF alignment with calendar-server.bounces.google.com which I suspect is the email server ...
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Why does my DMARC report from Google have "<dkim>fail</dkim>" when all auth_results have "pass"
We're using Microsoft 365 (outlook.office.com) for our company emails and have had DKIM set up for a while, but recently added a DMARC record. I now got a DMARC report from Google where every record ...
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DMARC without rua... proper format?
Yahoo and Google are now requiring DMARC according to Shopify. I have been setting them up for my clients, but I don't need the aggregate reporting. I only need it so that these companies can verify ...
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Incorrect dmarc record landing some mail in spam
I have just received notice from one of our partners that some of our emails sent via AWS SES are being flagged by their email provider as potential spoof DMARC.
We used route 53 to add all our DNS ...
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Postfix - Only allow relaying when sent from local user
At the moment, our Postfix + Dovecot mail system has two types of users: those with a full account and those with only a forwarder.
Users with a full account are in the virtual_aliases table pointing ...
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Should we add SPF records of popular email providers?
DMARC is reporting that a small fraction of our emails originate from google, microsoft, and some other providers.
DMARC is also reporting that a good chunk of those emails fail both SPF and DKIM, and ...
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DMARC and Postfix delivery reports
I successfully set up DMARC, DKIM and SPF for my mailserver's domain, but delivery reports created by Postfix fail the DKIM/SPF tests.
The headers of regular messages (sent via my mailserver) look ...
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253
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Sendmail unable to email to specific domain
I have a server running Sendmail and is able to email to all domains except my company's email (company1.com). I have tested to sending to gmail and other email providers with no issues. Sendmail is ...
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A Non-MX mail server + Google Workspace, is this viable?
I have a domain (example.com) configured for sending and receiving mail using Google Workspace. I need to launch additionally a separate (own) mail server. Switching completely to the new server is ...
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Should HELO, MAILFROM and From use the same domain?
I configured a mail server a couple of times before and I believe back then I thought
that the answer is "yes."
But I'm about to configure another one, and it seems that I was wrong. Let's ...
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Getting Spoofed - DMARC , DKIM and SPF are properly setup (AFIK)
I have been testing my DMARC policy for some weeks and I ran into this issue. Background:
SPF - setup and working
DKIM - set up and working (AFIK)
DMARC - set up and working - looking for alignments ...
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Email message headers pass SPF check after failing earlier SPF checks. Will this result in spam?
I have an issue where email is being marked as spam by Gmail/Google Apps systems.
When reading the mail headers, the most recent SPF check in the mail chain passes, but earlier checks fail. That is, ...
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Change mail from header in sendmail
We have two separate RTs (request trackers) configured on one server. They both are configured to send the emails through sendmail.
We are trying to configure now SPF and DMARC records for these DNS ...
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DMARC reports no longer being received from google
We are seeing a large number of DMARC rejects from google from emails that have both a valid DKIM signature and a valid SPF sender. We have validated this by sending the same emails to other ISPs and ...
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Mail server running on a subdomain - how could email acceptance by other servers be influenced by dns records for different ips?
I started to run a self-hosted mail server which I want to be reachable via a subdomain only. I have an A record for mail.sub.domain.tld and an MX record for sub.domain.tld /edit: which points to mail....
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How to setup DMARC for both AWS SES and Office 365
I'm trying to get DMARC working for the emails I send via Office 365 as well as Amazon SES. It's working for Office 365 because I setup the SPF and DKIM records in my DNS but it's failing for the ...
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Changing SPF record from ~all to -all where employee inboxes are with Google and Amazon SES is used for website transactional emails
I'm interested in moving from ~all to -all in my SPF record in order to lock down my domain emails a bit more, but I want to know what the impacts might be (I do understand at ~ is SOFTFAIL and - is ...
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Why does DMARC fail for forwarded emails from this particular domain when it passes for all other domains?
I run a virtual mail server that forwards emails to my domain to a Gmail address, and I use PostSRSd to rewrite the addresses. For example, if someone sends an email to [email protected], my mail ...
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Hotmail does not flag or remove phishing messages from email addresses on a domain with SPF enabled [closed]
The email address of the sender of our newsletter is used for phishing purposes. We do have a valid SPF record (ends with -all) and dmarc on our domain (confirmed by mxtoolbox.com : every checks are ...
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Mail proxy with SPF and DMARC without changing FROM headers
Here is my situation.
We have internal network, with lots of 2nd level subdomains - foo.internal.domain.ltd as example.
Those subdomains may or may not have public DNS records with Class A IPs.
Then, ...
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DKIM and how it relates to DMARC reports
I've been tasked with setting up DKIM, SPF and DMARC for a business. I come from more of a development background, so as a result, I've been a bit confused on how to interpret the DMARC reports I'm ...
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Which has bigger priority between DMARC and SPF?
First off let me start by saying I understand DMARC and SPF do not do the same thing.
However both have an option to tell the receiving servers what to do with mails that do not pass SPF (and DKIM in ...
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DNS Records - CNAME
Quite newbie, so sorry any unconnected data. I am creating a DKIM and SPF records to emulate DMARC as a workaround. An external vendor of us, want to send emails under our domain using a subdomain.
I ...
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Apparent DMARC External Validation query failure
I've got multiple domains hosted on a single Linode instance. As a result of some routine anti-spam checking the wonderful mxtoolbox (no affiliation) reports this:
DMARC External Validation External ...
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DMARC rua unable to send reports via sendmail to local e-mail address?
I've setup a small mail server with Postfix, Dovecot, and MySQL (MariaDB) on Debian. I've also configured TLS with Let's Encrypt. rDNS, DMARC, DKIM, SPF and Fail2Ban are also setup and confirmed to ...
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How do i receive DMARC reports with external domains that i have no permission to control
I want to receive reports with gmail or outlook or anything else that i have no permission to add (mydomain.com)._report._dmarc.(gmail|outlook).com as a record. What i can do?
Example just like:
v=...
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786
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DKIM E-Mail verification - prevent receivers from accepting unsigned emails?
I have set up SPF, DKIM and DMARC in my domain (to the best that I can figure out), but I still can send spoofed emails - without a DKIM signature - and they are accepted (at least when I test with ...
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I setup DMARC p=reject on server but now I can't send via gmail to gmail (using server email From address)
Did I shoot myself in the foot ?
I mainly use gmail to send and receive emails. Support etc. My default 'send email as' profile is not the gmail address itself but an address on my server (also the ...
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How to proper dns zone config for selfhosted email server
Looking to harden the sending authentication of my email server, I am looking for some usefull hints on the topic.
As I have in total 4 Vps Servers where emails will be send from, registration ...
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Should we enhance DMARC to allow aligned DKIM enforcement?
Currently, DMARC only requires aligned DKIM or SPF.
However spoofing SPF is relatively simple for an experienced hacker:
You should only control a single IP address in the often large SPF range of e-...
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I don't understand DMARC reports regarding my policy
My DMARC settings seems to not work as expected.
First, a few things to note:
The domain is mydomain.com (not the real one obviously) ;
The domain and mail provider is gandi.net ;
I use Amazon SES to ...
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Send bulk emails with valid DMARC security
We are implementing a feedback feature in our web application. After completion of an event, we are sending emails requesting feedback and ratings to our visitors.
If we do write the following DMARC ...
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Correct SPF record
I have been asked to apply DMARC protection to a domain. Part of this requires me to add an DNS record to the domain management console, however I have come across a stumbling block. The DMARC checker ...
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How to prevent calendar invite responses from being blocked between two Google Workspace accounts?
My company has two separate Google Workspace accounts, each associated with a separate domain (lets call them domainA and domainB).
Employees have email addresses assigned to them for both domains.
If ...
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