9
votes
Accepted
Why is google.com trying to send emails from my domain?
Short Answer: You're seeing internally routed emails in your DMARC reports, for recipient domains hosted on Google GSuite.
From the screenshot you share, it seems like these emails sent from Google ...
- 490
4
votes
Accepted
How to find the DKIM selector without being the owner of the domain?
I assume your client has sent an email to you at some stage, in the headers search for ‘DKIM-Signature’ to find the DKIM signature applied to the message.
This DKIM-Signature contains an attribute ‘s=’...
- 8,511
4
votes
Accepted
Yahoo rejecting email after registrar change
The problem could be IP reputation. The message is rather clear. The specific IP address (209.182.201.150, I assume it's your mail server) is being rejected.
Plus, that IP address is present in at ...
- 1,133
4
votes
Setting up DKIM, SPF, and DMARC Records for Domains that You Won't Use for Email
If these domains are related to your company or brand, you want to prevent bad actors to be able to abuse these domains.
For SPF you may publish the following records in DNS:
@ IN TXT "v=spf1 -...
- 490
3
votes
Sent emails pass SPF and DKIM, but fail DMARC when received by Gmail
The issue is caused by inconsistent between return-path and header From:.
Return-Path: mandrillapp.com
From: @seesawsf.com
SPF and DKIM check the domain using RFC5321.MailFrom (generally Return-...
- 31
3
votes
Why is google.com trying to send emails from my domain?
Did you accept or reject a Google calendar invite? The creator of the event will get an email from Google using your email address as 'from' address.
Might be the case for other services offered by ...
- 983
2
votes
Accepted
Can I delete TXT record after DKIM configuration?
No. The recipient's email server verify this via a reverse-DNS lookup to prevent spoofing.
--> expanded my answer upon the advise of Stephen Ostermiller
The DKIM needed to be set up at 2 locations:
...
- 156
2
votes
Accepted
How do email spam filters tell if a spam email was maliciously sent with intent to shutdown a real email address?
Spam filters cannot definitively tell that the second email is not from the legitimate user unless an SPF record exists to inform them of the only authorised servers for sending messages.
The ...
- 3,013
2
votes
DMARC failure on forwarded SharePoint Online emails
The way I understand it, DKIM and SPF are passing but DMARC is failing
because the header.d address does not match the header.from address.
Is that about right?
Yes it is. The same goes for SPF, ...
- 490
2
votes
Accepted
If I have 2 services sending email using my domain name, can I set up DKIM for one but not the other?
It is totally fine to send mail using two ESPs (Email Service Providers) and only use DKIM with one of them.
The one that has DKIM will benefit from better deliverability. It won't be dragged down by ...
- 16.3k
2
votes
Do subdomains inherit DKIM keys? Can a DKIM SDID for one domain be used to validly sign mail that appears to be sent from another domain?
There is no inheritance.
RFC 6376 §3.6.2.1:
All DKIM keys are stored in a subdomain named "_domainkey". Given a
DKIM-Signature field with a "d=" tag of "example.com" ...
- 8,485
2
votes
Intermittent DKIM authentication failing
What would cause this [25% of those messages failing both authentication and alignment]...
Failing authentication is obvious. DKIM signatures in emails don't validate.
Failing DMARC alignments means ...
- 101
2
votes
How to handle duplicate DKIM selectors?
DKIM selectors are arbitrary strings. They're used to locate the corresponding public key on the DNS, and can virtually be anything that is valid as a DNS label.
Having said that, selectors provided ...
- 101
2
votes
Accepted
Setting up DMARC and DKIM for subdomains not hosted on the same server as the main domain
The subdomains may be hosted on server B, but DNS records are stored on the server where the nameservers are pointing.
So you should be setting them up on Server A.
- 8,511
2
votes
Yahoo rejecting email after registrar change
UPDATE:
This problem currently appears to be resolved. Emails appear to be working again. It may have just been Yahoo or even blacklisting as Kate has suggested. It's not the first time we've seen ...
- 3,290
1
vote
Can I replace rua entry with ruf in DMARC record?
The ruf directive is generally unsupported by email providers, so you will likely miss a lot of reports if you don't include an rua directive.
In other words, regardless of whether it's valid syntax ...
- 16.3k
1
vote
Accepted
Is DMARC relaxed alignment for SPF/DKIM bad?
Relaxed Alignment let's you authenticate your FROM domain by using a subdomain in your DKIM signature (d=sub.domain.tld) or Return-Path address ([email protected]).
This is very useful for ...
- 490
1
vote
Do subdomains inherit DKIM keys? Can a DKIM SDID for one domain be used to validly sign mail that appears to be sent from another domain?
From rfc-editor
3.10. Signing by Parent Domains
In some circumstances, it is desirable for a domain to apply a
signature on behalf of any of its subdomains without the need to
maintain separate ...
- 11
1
vote
Accepted
Do subdomains inherit DKIM keys? Can a DKIM SDID for one domain be used to validly sign mail that appears to be sent from another domain?
Re the first question: As mentioned in Patrick's answer, there is no inheritance.
Re the second question: I've now realised that DKIM doesn't specify which SDIDs are permitted for particular email ...
- 189
1
vote
DMARC report: systematic SPF failure for a domain
bounce.domain.co.uk should have an SPF record in order to pass authentication check
and header from domain should be equal or aligned with bounce.domain.co.uk in order to pass DMARC check
- 21
1
vote
DKIM fails in DMARC report but not when checked independantly
I ended up switching my key from 2048-bit to 1024-bit and now it passes. I'm not sure at all why this is, but it works.
- 21
1
vote
DKIM fails for Gmail only. Emails in spam
Had same problem.
helped this post: https://www.hmailserver.com/forum/viewtopic.php?t=27904
Changing BOTH 'Header Method' and 'Body Method' to the default
'relaxed' instantly made my DKIM ...
- 119
1
vote
Are SPF and DKIM records needed when the SMTP IP is marked as a subscriber block?
I'd say DKIM is definitely a value adder in this scenario!
Different ESPs have different ways of handling block / black lists. However, email authentication is gaining traction.
Apart from the proof ...
- 490
1
vote
Are SPF and DKIM records needed when the SMTP IP is marked as a subscriber block?
While every domain should have SPF configured in the DNS records to identify the servers that are allowed to send emails for the domain I doubt that adding DKIM will make a huge difference as you are ...
- 10.2k
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