Set up DMARC with Constant Contact

Constant Contact calls it « self-authentication »: signing with your own domain rather than theirs. Two methods exist, and the choice is not a matter of preference — it depends on how many accounts send from your domain.

The recommended method: CNAME

From advanced settings, choose Self-authenticate using DKIM CNAME records, select your domain, and Constant Contact provides the CNAMEs plus a DMARC record if you do not have one yet.

Allow 24 to 48 hours for propagation, then return to advanced settings and click Check status. The domain moves to « Activated » — that label, not the presence of the records, is what confirms it works.

The case that rules out CNAME

If several Constant Contact accounts send from the same domain, the CNAME method fails: one host name cannot point at several targets. You then have to use the TXT method, repeated for each account.

That case is more common than it looks: a company with a marketing account and an events account, an agency managing a client’s domain, a subsidiary on the group domain. The failure does not say why; it is almost always this.

A domain address, not a free one

Self-authentication requires an address on a domain you own. Free webmail addresses — Gmail, Yahoo, Outlook — are not eligible: you do not control their DNS zone, so you cannot publish anything in it.

DMARC

Publish the monitoring policy on _dmarc.yourdomain.com:

v=DMARC1; p=none; rua=mailto:your-address@yourdomain.com

Only tighten once every sender is identified. The progression, step by step.

Common mistakes with Constant Contact

• Insisting on CNAME with several accounts. You have to switch to the TXT method; there is no alternative.
• Stopping at the published records. Until the status reads « Activated » in the interface, the authentication is not in effect.
• Checking before 24 hours. Constant Contact states 24 to 48 hours itself: a check the same evening proves nothing.
• Trying with a Gmail or Outlook address. Not eligible by construction.

Once it is in place, Clarsend reads your reports and shows you what passes, what fails, and who is sending without your knowledge.