In the ongoing effort to combat unsolicited bulk emails being sent to their domains, many of the larger email hosting platforms like Google, Microsoft, and Yahoo are introducing new requirements to verify that emails being sent to their customer’s accounts are legitimate. These requirements are mostly for organizations who send thousands of emails each day but are still important to anyone sending email from their own domain (email@mydomain.com).
Even if your business isn’t a big sender of mass email marketing messages, there are some basic technical steps you can take to make sure email messages sent from your domain name make it to their intended recipient.
The most important is to ensure your email messages are authenticated by adding some information to your domain name’s DNS records.
Warning: If you have never made changes to your domain name’s DNS record, then hire a professional to help you.
The three records you can add to your DNS record to help with email authentication are SPF, DKIM, and DMARC. All are added as TXT records.
SPF (Sender Policy Framework)
This setting identifies which mail servers are authorized to send an email on the domain.
Example DNS Entry:
Type: TXT Name: domainname.com Value: v=spf1 +a +mx +ip4:ServerIpAddressGoesHere include:mymailserver.domain.com ~all
DKIM (DomainKeys Identified Email)
This setting is used to include a digital signature on an email which can be used by a receiving mail server to verify the message’s authenticity.
Your email hosting provider will have to provide you with the information you need as they have to generate the signature.
Example DNS Entry:
Type: TXT Name: default._domainkey.domainname.com Value: v=DKIM1; k=rsa; p=EncryptionSignatureGoesHere;
DMARC (Domain-based Messaging Authentication, Reporting and Conformance)
Your DMARC setting takes your SPF and DKIM settings into consideration and informs mail servers what they should do with the message if the sender didn’t pass authentication. This setting is helpful for getting reports on activity using your email domain.
Example DNS Entry:
Type: TXT Name: _dmarc.domainname.com Value: v=DMARC1; p=none; rua=mailto:reportemail@domainname.com
Some additional helpful information:
- SiteGround KB articles: SPF & DKIM
- Valimail: A company providing automated, aggregate DMARC reporting.
- MXToolbox: Their ‘SuperTool’ can help you check your various DNS settings.