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I recently saw that cpanel has new entry for

DKIM (DomainKeys Identified Mail) 


The SPF (Sender Policy Framework).

They seems to be talk about a mail/spam prevention, etc

I would like to know what are they ? How they work ..

How to set up this kind of a more reliable mail server ..

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migrated from Jun 3 '12 at 9:54

This question came from our site for professional and enthusiast programmers.

Which of the various Google hits did you read? What was confusing about them? – ghoti Jun 3 '12 at 3:23
how do i set up a one for my domains ? i broght from godaddy and i ahve my own dedicated server not sure how to do set it up ? – user1179459 Jun 3 '12 at 3:27

DKIM and SPF are tools that ISPs use to verify that emails are legitimate and prevent forgery. Although neither is explicitly required, having them significantly improves your emails' deliverability. And if you use an outside email provider like SendGrid, usually DKIM and SPF are necessary for whitelabeling your domain.


DKIM is used to prove that the domain that the email is coming from is actually allowed to send those emails. The sender of the email publishes a private key and the domain owner publishes a public key in their DNS. When combined, they authenticate the sender's ability to send emails from the specified domain.

If the domain that the email comes from doesn't match up with the DKIM record, many email providers will put an "on behalf of XXX" note next to the senders name. I know for a fact Gmail and Hotmail both do this.


Sender Policy Framework is another DNS record that helps prevent forgery. The domain owner publishes a list of outgoing mail servers that are allowed to send on its behalf. If they don't match up, the message is typically marked as spam.

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In a very short explanation:

DKIM is a public key that identify email sent from you domain.

SPF is a list of authorized domains which can send email for your domain.

The DKIM was created by Yahoo! but aren't widely used. The SPF is largely used, but almost all server fail silently, so it isn't a good one too.

Both are DNS records that you add to your domain and both are way to make your server reliable, these will not avoid you to get spam.

Look for this link for good ways to improve your email server:

Hotmail Postmaster

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