Questions tagged [dkim]
DomainKeys Identified Mail is a scheme for signing and verifying email messages to confirm that that the source hasn't been forged, and is typically implemented by MTAs. The source MTA adds a header to the message body containing a signature, and the destination MTA verifies this signature against a key retrieved from DNS.
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opendkim-testkey: key not secure
I set up Opendkim milter to work with postfix on my machine. Now email is signed & verified correctly i.e. email source code shows DKIM-Signature header.
TXT record on the authorative dns is set ...
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DKIM - key pair generation recommendations
I wonder if it is okay to generate a key pair (.key and .cert files) for DKIM like this:
openssl req -newkey rsa:2048 -sha256 -x509 -nodes -days 3650 -keyout dkim-rsa.key -out dkim-rsa.cert
By ...
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Would adding CNAME records in DNS server for setting up DKIM cause email server issues?
I want to add two CNAME records to make my Microsoft exchange be DKIM compliant according to Microsoft.com’s instructions.
Is there any possibility adding the two CNAME records would cause disruptions ...
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SPAM Domain Spoofing through SES
A spammer seems to be running spam through SES and spoofing our domain.
We are using SPF and DKIM so I’m not sure what is going on.
This is our SPF record:
v=spf1 a mx include:amazonses.com include:...
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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 ...
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How to setup same DKIM setings for multiple servers
I have three servers configured to relay mail. I am using dkim-milter with postfix on CentOS 5.5. I created domain keys on the command line for each server. My issue is that the domain key is ...
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System to prove content of a DNS record/DKIM key at a certain time?
I'm trying to build a way to prove that an e-mail was indeed sent from a specific domain.
Is there a service that allows me to demonstrate what value a TXT record had at a certain time, e.g. by ...
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intermittent DKIM failure
We have several email servers that send out legitmate email via PostFix and use openDKIM.
Recently we've had some recievers claim the DKIM record can not be verified so we've tried various tools such ...
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DKIM and subdomains
We use a sub domain "mail.domain.com" for sending marketing emails from Salesforce Marketing Cloud, the reason it was set up this way is to keep the reputation of this domain separate from ...
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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 ...
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DKIM and multiple Email protection Gateways
Just wondering if anyone has ever setup DKIM with multiple email protection gateways
We are running with 365 and a couple of email protection gateways in front
Do you need to add the public key to ...
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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 ...
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How to set Public Key DKIM in Postfix
I need to set up my public key in the postfix server, I already generated the keys in https://dkimcore.org/tools/, and added the TXT records in my DNS provider. But I have no idea how to set it in my ...
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Email protected with SPF but received valid signature from other IP anyway
I've received an email in spam from [email protected] to [email protected], but the "sent by" came from rec15.appleandrdoidmail.mx. [email protected] is an alias. Weird thing is that it says ...
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OpenDKIM not signing but no error
I've set up opendkim (2.10) with postfix on an ubuntu 16.04 host. According to the logs, all is fine (i.e., no errors), but mail isn't being signed. I can see that postfix is passing messages to ...
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DKIM Key Rotation Best Practices
Do you find it necessary to regenerate your DKIM keys every 1-6 months to avoid your mail going into the receiving servers' junk mail folder?
Some guides recommend this, some even say it's "Best ...
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Issue with opendkim key not valid in dns check
I am checking the dkim key generated by opendkim and I keep getting an error of key not valid. Here is the output of mail.txt key file:
I replaced my domain with example.com in this scenario.
mail....
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DKIM cname record name (generated by AWS SES) is > 63 characters which exceeds the DNS limit
i am working on a client site that has a long domain name (25 characters). when setting up AWS SES i am unable to update the CNAME DKIM records on the DNS provider as the maximum length allowed for ...
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Modifying date breaks DKIM signature. Alternatives?
On our Postfix server we previously removed the Date header from incoming emails and had Postfix automatically add it again to prevent spoofing the date and to work around mail servers with off clocks....
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SPF and DMARC - is spf policy used?
I understand how SPF is involved with DMARC alignment, but one thing I can't get clear: is the SPF policy (-all or ~all) used in DMARC? Or does DMARC merely use the IP ranges?
The issue is, that as ...
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OpenDKIM query timed out (even with opendkim-testkey and Nameservers set)
I try to set up a mail server on Debian with opendkim and opendmarc
When I receive an email, SpamAssassin refuse it because opendkim can't do the DNS query
I tested with opendkim-testkey command, ...
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Transactional Emails from my server goes directly to Spam folder of users in Yahoo
I am trying to setup our website portal to send registration confirmation emails to customers who sign up (its a simple message containing a link that confirms the email of the user).
Everything is ...
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SPF and DKIM for one domain on two servers [closed]
I followed this guide to setup SPF and DKIM for emails to be sent from a server for a domain. That server is the location of the actual email server for the domain.
I now want to setup another server ...
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VERP: rewrite from header of NDR?
We provide cmail delivery for external clients from several different domains.
We rewrite the envelope sender (AKA: "SMTP MAIL FROM","Return-Path" ) using a form of VERP. Thus we ...
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Correct DKIM, Reverse DNS configuration to send from 2 different domains?
I have set up Postfix on an Ubuntu 18.04, with a view to sending emails from two different domains, which I will refer to here as abc.com and xyz.com. I'm trying to configure everything so that emails ...
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RSPAMD + DKIM Signing: How to be able to use a single DKIM Key for multiple domains?
I was able to setup a Single DKIM Key for multiple domains with OPENDKIM by using their KeyTables and SigningTable. But since the company started to use RSPAMD, I could not use OPENDKIM along with ...
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Does absence of SPF, DKIM, DMARC records on a domain affect the email delivery?
Say, I don't have these records for a domain at all and the email delivery is OK.
Will those records improve something regarding the delivery or are they just a remedy for domain spoofing and are not ...
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Is SPF alignment important with DMARC?
When setting up a DMARC policy for an organization, is it important at all to have SPF alignment?
I've gathered that:
Most email service providers support DKIM for a custom domain.
Not all email ...
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How can I fix emails being marked as spam after being edited by Postfix?
Recently, I set up a Linux server running Postfix that I'm using to send and relay emails. I've also set up an email address that's used as an alias and forwards the emails to another email address, ...
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Exim4 does not add DKIM signature
Have spent 2 days trying to tell Exim to add DKIM signatures on my Debian8 server. No success. Have read many how-tos, forums but none of possible solutions wotk on my server.
Have generated the keys:...
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Can I DKIM sign my email without running a server daemon just for that?
I have an email server that is working perfectly.
However, more and more other email servers are getting strict about DKIM signing and DMARC records so I guess I need to finally set that up ...
I am ...
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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 ...
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Change From (Sender) address using Postfix as a relay and pass validation
I'm trying to relay mail via Postfix and change the sender address whilst also passing DKIM/DMARC validation.
So if I send an email from [email protected] via the Postfix relay (using it as a smart ...
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How to add DKIM feature to the IIS 7.5 - Windows Server 2008 - DomainKeys Identified Mail
How to add DKIM feature to the IIS 7.5 - Windows Server 2008
DomainKeys Identified Mail
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Postfix working on separate server having issues delivering mail to a specific domain
I have the following situation.
My main domain is pointed to a Hostgator account. Because of bad performance of the site, the client decided to give DigitalOcean a go, but leaving the e-mails on ...
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How to implement DKIM for Domino mail server?
I'd like to write a Domino servlet that will stamp outgoing mail with a DKIM domain keys signature. We would generate the Domino mail server DKIM signature and put it in a TXT file with the DNS ...
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DKIM header exists but signature is not valid
UPDATE
Now the validator at mail-tester.com says the DKIM signature is fine.
On the other hand the isnotspam.com still doesn't seem to like it.
I assume it is working fine now. Also gmail accepts ...
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Setting up SPF record for A2Hosting shared hosting
I'm trying to setup A2Hosting SPF correctly since the proposed SPF is landing the emails in the SPAM folder in Gmail.
This is the default SPF: v=spf1 +mx +a +ip4:210.125.99.77 ~all
But when ...
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How does DKIM work when sending emails from multiple sources/servers?
So if I'm understanding DKIM correctly, it basically is a public/private key type of service. However, how does this work if you send emails from multiple servers/sources? For instance, I have a ...
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SPF hardfail and DKIM failure when recipient has e-mail forwarding
I configured hardfail SPF for my domain and DKIM message signing on my SMTP server. Since this is the only SMTP server that should be used for outgoing mail from my domain, I didn't foresee any ...
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what is the appropriate DMARC configuration for a domain that should fail hard on DKIM but soft on SPF
Messages sent by my domain will always be DKIM-signed and any that are not should be immediately discarded by recipients. But strict SPF enforcement leads to problems where internal mail-forwarding ...
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SPF- and DKIM- align fails on a few emails from a larger batch
We are sending large numbers of emails (hundreds of thousands) mostly for our clients. Of course, we have configures SPF, DKIM, and DMARC records properly for all domains who use us. We pass all tests ...
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With valid SPF, DKIM, and DMAR, Office 365 email still goes to junk mail and got Authentication-Results-Original: spf=none
My goal is to be able to send email from my website using smtp.office365.com and the emails will go into inbox instead of junk mail. But so far, I have not succeed.
If the receipt is gmail, the ...
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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. ...
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DKIM validating, but mxtoolbox reports as "DKIM-Signature Not Verified"?
I'm trying to figure out why a lot of emails from one of my sites are not getting through (in particular sky.com and gmail.com).
With my server, we have a tool that generates the DNS records for us:
...
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SMTP DKIM for 1 add-on domain on 2 servers
Is there a more practical way for SMTP DKIM signing for a VPS server that has a parked domain but does not host the content other than private key copying?
I have looked all over Server Fault but ...
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DKIM with same key but different domains
We are planning to sign with DKIM emails for multiple domains.
Each domain will have a CNAME to a DNS entry in a common domain where the keys are stored.
If every domain sign with the same key, but ...
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locking down with DKIM and SPF and received email that looks signed by our DKIM
We received this email which is definitely spam/spoofing our stuff(I don't have DMARC setup just yet and haven't finished setting up DKIM on one other service sending email for us). I don't get how ...
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DKIM failure "message has been altered"
Summary
I have a Mattermost server which needs to send emails out to users when they sign up, etc. These emails are failing DKIM checks and showing up in users' Gmail as spam.
Observed behavior
I ...
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DKIM set on AWS EC2 but mail header says none in Outlook
I'm configuring an AWS EC2 instance with Postfix, and have set it up with Route53 including reverse DNS. I've tested that I can send emails, and Outlook receives them fine, but Gmail does not. I ...