Email Authentication through SPF and DKIM

Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) are email authentication methods to prevent email spoofing.  For this reason, some email hosts are beginning to require one or both be added to avoid mail rejection.

Please note that we are currently rolling out updates to SmarterMail which updates the interface.  The first set of DKIM instructions are for the legacy interface.  For the updated interface, scroll down passed the (Legacy) instructions to the (New) instructions. 

A SPF is defined by adding a TXT record to the domain's DNS.  The SPF for sending mail through Winhost is:

v=spf1 include:internetmailserver.net -all

If hosting DNS through Winhost, the SPF record would be added through the DNS Manager:  Winhost Control Panel > Domains > Manage (DNS) > Manage TXT Record > Add

Domain Name: Field is left blank

Data: v=spf1 include:internetmailserver.net -all

TTL: 3600

 

Like with other DNS record updates, it will take some time for propagation to complete.  To monitor DNS propagation https://www.whatsmydns.net/ may be used.

To test the SPF record, see the Testing SPF and DKIM section below.

DKIM is a combination of a SmarterMail setting and TXT record.

First log into the SmarterMail web interface as the domain administrator (default is postmaster).  If the web interface address or password isn't known, log in automatically at:  Winhost Control Panel > Sites > the applicable domain name > Email > SmarterMail Manager

(Legacy) Once logged into the webmail interface, click Domain Settings (gear icon with globe), General, and then the Enable button in the Email Signing pane.

 

(New) Once logged into the webmail interface, click the More1 drop-down and then Domain Settings2.

(New continued) Then select General1 and then the Enable2 button.

After clicking Enable, a pop-up with a TXT record will be displayed.  Add the TXT record to the domain's DNS, allow time for DNS propagation, then click the Enable button once more.

If hosting DNS through Winhost, in a separate window navigate to the DNS Manager: Winhost Control Panel > Domains > Manage (DNS) > Manage TXT Record > Add

Domain Name: The "Text Record Name"

Data: The "Text Record Value"

TTL: 3600

DNS propagation can be reviewed at https://www.whatsmydns.net/.  If checking propagation of the TXT record for DKIM, make sure to enter the entire Text Record Name (textBlock._domainKey.domain.com in the example above) into the domain field on whatsmydns.  Then select TXT from the drop-down and Search.

After the DNS record has propagated, clicking the Enable button for Email Signing will update the pane with a message that DKIM is running on the domain.  If after an hour the Enable button still shows the pop up with the TXT record value, double check that the complete TXT record has been added to the domain's DNS.  Or open a ticket with the Support Department for assistance in reviewing the DKIM.

A simple test of the SPF and DKIM can be performed by sending an email to a Gmail recipient and checking the email header.  After the email is received, view it, click the three vertical dots for more options then Show Original.

If set up properly, there should now be two PASS notifications on the Original Message page.