Usually we'll authenticate our domain in Dynamics 365 for marketing application to send marketing emails .
But we might need to send marketing emails by subdomain to keep our root domain reputation, this article will shows how to authenticate a subdomain in marketing settings.

Add subdomain

For example: email.rootdomain

Overview of ownership authentication key and email authentication keys for DKIM


In lower section, value field is namekey1subdomain.marketing.dynamics.com;
while in authentication for root domain, the field will be:
namekey1domain.marketing.dynamics.com
We need to pay attention to Host field, which may confuse us because it's still namekey1._domainkey. Due to we want to authenticate subdomain, so the real value should be namekey1._domainkey.email when we add the record in DNS settings.

Our own domain DNS settings

UI would be different for different domain providers, but points are same.

  1. Add a TXT record for subdomain.
  2. Add correct CNAME records for subdomain namekey1._domainkey.email.

Result