Setting up a sender domain

Mailings can be sent from any address, like This address can be manually set in Copernica, but to make sure all recipients receive the mail correctly, we advise to update your DNS settings first before sending mail through Copernica. Simply put: your domain's DNS settings need to say Copernica is allowed to send mail from your domain. If this is not the case, chances are many of your messages will not be accepted by recipients' servers.

Normally, setting DNS records is a complex thing. It involves correctly creating records for SPF, DKIM and DMARC (we'll explain later on what all of these mean) and subdomains for click, open and bounce tracking. If you want to do this correctly, you'll also need to rotate these settings periodically to make sure your private keys don't get cracked. Copernica has an easy solution for all of this called Sender Domains, which makes managing your DNS settings a lot easier.

Marketing Suite or Copernica Publisher?

The sender domain technology is available in both Publisher and MarketingSuite, although the interface in MarketingSuite offers you a lot more insight. Therefore, the MarketingSuite is more suitable for managing sender domains.

When you set up your domain as a sender domain, Copernica automatically makes sure your DNS settings are correct and up-to-date. You won't need to configure anything, domain-wise, after the initial setup. This means your click, bounce and open domains are set up and your DKIM keys are rotated automatically. The Publisher still has forms to manually set up DKIM keys and subdomains, but these are no longer necessary. The sender domain settings override these, even if you choose to only send mail through the Publisher.

Top-level domain or subdomain?

Setting up a sender domain requires you to fill in a domain name. This is the domain you're going to use for the sender address. For example, if you want to use, you register as the sender domain. After that, a number of relevant DNS settings will automatically be generated by Copernica. Note that if you already had SPF, DKIM or DMARC settings in the DNS of your domain, you'll need to transfer these to the sender domain. If you don't want to do this, because you don't know how or because you're afraid something will go wrong, it's best to use a subdomain. This could be something like, or whatever you want it to be. While this may look less fancy, it is the fastest way to fix the configuration quickly if you want to start sending mail.

Validating your domain

To prevent abuse of sender domains, you need to prove that you're really the owner of the domain. After registering your sender domain, MarketingSuite shows a warning message. You first need to add a TXT record to your DNS with a code only Copernica can decypher. Only after we've seen this record in your DNS, we'll believe it's truly your domain. You'll be able to complete your setup after this.

Background information

As described above, Copernica creates all relevant DNS settings so you don't need to. However, Copernica cannot implement these settings for you. No one except the domain owner has writing rights to DNS settings unless the owner explicitly grants permission. The domain owner is the only one who can add subdomains and records to a DNS. At this point you're probably wondering how we can do so anyway.

Here's the deal: the DNS settings Copernica sets up and manages are not actually settings for your domain, but for a subdomain of Copernica itself. The settings we offer in the MarketingSuite are recommended settings containing aliases that point to Copernica's DNS. You need to copy these to your DNS so Copernica can manage your domains through our servers (because your subdomain links to our subdomain).

    Reccomended settings that                DNS records on Copernica's
    need to be added to the DNS:             server, with sender domain

    +-------------------+                       +-------------------+
    |   SPF alias       |           --->        |   TXT record      |
    +-------------------+                       +-------------------+
    |   DKIM alias      |           --->        |   TXT record      |
    +-------------------+                       +-------------------+
    |   DMARC alias     |           --->        |   TXT record      |
    +-------------------+                       +-------------------+
    |   Tracking alias  |           --->        |   A record(s)     |
    +-------------------+                       +-------------------+
    |   Bounce alias    |           --->        |   MX record(s)    |
    +-------------------+                       +-------------------+

After registering and validating your domain and adding the aliases to your DNS, you can start sending mailings that are properly authenticated and using aligned domains.

The next step

To send your first mailing, you need a database with profiles to send it to.

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