DMARC

DMARC (“Domain-based Message Authentication, Reporting & Conformance”) is a further email authentication protocol that works on top of SPF and/or DKIM records. For emails sent through emfluence, if you have an existing DMARC record and you are passing DKIM as described here, DMARC should also pass in most instances.

As of February 2024, Google and Yahoo! are requiring any bulk senders sending more than 5,000 messages a day to have DMARC policy in place. Messages not passing DMARC may not be delivered.

To check whether or not your domain has a DMARC record in place you either use the sending domain checker in emfluence in the Options menu or use a public  DMARC checker such as those provided by dmarcian or MxToolbox.
 

If those records do not exist, someone with access to your DNS will need to add a DMARC TXT record. If you are not ready to take full advantage of the security aspects of DMARC you can put a simple record in place with a policy of "none" which would still satisfy the need to have a DMARC record in place.

The makeup of the record includes multiple tags which perform different actions. Information on the different tags can be found here. Some information about how a DMARC record is constructed can be found here. This generator can also help you build a record. It is strongly advised that you coordinate with your IT department as DMARC records impact ALL email from the domain, not just those from emfluence.

The most simple DMARC record that wouldn't quarantine or reject contacts or send notifications but would still meet the minimum for what Gmail and Yahoo! are looking for would be:

Type: TXT 
Name: _dmarc.{your_sending_domain}
Value: v=DMARC1; p=none;