Skip to main content
The 2026 Annual Developer Survey is live— take the Survey today!.

Questions tagged [spf]

Ask Question

Sender Policy Framework is a standard by which the owner of a domain uses a specially formed DNS record to advertise which hosts are authorized to send email for the domain.

923 questions
Newest Active Bountied Unanswered
Score of 1
2 answers
210 views

I'm having a problem with my SPF. Looking in mxtoolbox.com for my SPF record, I get the error Too many included lookups. I should have to remove some of my 'include' options or try to flatten some of ...
Score of 1
5 answers
238 views

I am wondering how feasible it is to send email with a DKIM-only setup, with an SPF record of v=spf1 -all. If my DMARC policy requires DKIM alignment then recipients who understand DMARC will still ...
Score of 0
1 answer
52 views

SPF configuration for all my domains works, but fails for DSNs sent by my mail server. The headers for a regular message look like this: Authentication-Results: posteo.de; dmarc=pass (p=reject dis=...
Score of 10
2 answers
577 views

I'm having trouble setting up SPF for my domain. I use email marketing services, but I keep getting SPF errors when sending emails. For example, one of the errors looks like this: 185.225... - SPF ...
Score of 1
1 answer
201 views

I have an Exim4 server on Ubuntu24 server. This mx has a mysql connection to get list of mailboxes and redirects to serve, in case of redirect I need SRS to avoid SPF failure on redirect. To enable ...
Score of 1
0 answers
111 views

I have a unbound server with DNS rebinding protection activated. However, due to the SPF "exists:" mechanism, some (stupid) mailproviders put 127.0.0.1 there when any IP would suffice. I now ...
Score of 0
1 answer
248 views

I need to set up an SPF record on a subdomain to plug a security vulnerability. However, I cannot simply set up a TXT record with the subdomain name as a CNAME record already exists with this name. In ...
Score of 1
1 answer
722 views

We are using Microsoft 365 Exchange Online to send email from our domain techoffice.ca. Over the last several days, emails to Gmail users are being rejected with the following bounce message: 550-5.7....
Score of 0
1 answer
271 views

How do I prevent this message: "Be careful with this message. The sender hasn't authenticated this message so Gmail can't verify ..." I have set up the following DNS TXT records: Name = @ ...
Score of 0
0 answers
164 views

I manage multiple domains (through ovh.com) including an internationalized domain (IDN), let's call it ïdn.com. The DNS records of these domains are relatively simple/minimal. They are all configured ...
Score of 0
0 answers
75 views

I'm running postfix and I'm having emails rejected by opendmarc that appear to be valid. Here is an example: Apr 9 17:51:40 primary postfix/smtpd[517925]: D4FAB20161: client=lg95.mta.exacttarget.com[...
Score of 0
1 answer
218 views

We have implemented DMARC (Domain-based Message Authentication, Reporting, and Conformance) with a "p=reject" policy to enhance email security and prevent spoofing for our business domain. ...
Score of 1
1 answer
82 views

Doing an include on domain A.example will also include all the domains that domain A.example has in it's spf records. So if I want to give A.example permission to send email on my behalf I'm also ...
Score of 0
0 answers
82 views

I am trying to troubleshoot a DNS (DMARC DKIM) issue and am stuck. My gut tells me that its a DNS issue where DKIM is not resolving correctly. But I don't understand how or why? So, we use a 3rd party ...
Score of 0
1 answer
71 views

Let's say I have a domain : example.com I also have a sub-domain : test.example.com If I have IPv4 values in the SPF record for the parent domain but don't have any IPv4 values in the SPF record for ...

15 30 50 per page
1
2 3 4 5
…
62