The DKIM record is missing. This is easy to fix. Here is a bit of background information and what to do next.

What is DKIM

DKIM is one of the ways to authenticate email communication by adding an encrypted signature to your emails. Some information (our DKIM public Key) is added to your Web domain settings, and a specific signature is added to all the emails that we send for you. This signature is encrypted based on some elements of the email being sent and, for this reason, it is unique for each email. When the receiving mail server analyzes your email, it will decrypt the signature using the public key mentioned above and It will generate a new hash string based on the same elements. If the decrypted signature matches the newly generated hash string then the email is considered DKIM authenticated.

What happens if it's missing

If your emails are not authenticated by you, we will authenticate them for you. This will help with deliverability, but will result in some email clients showing "On behalf of..." or "Via..." next to your sender information. That's because email programs want to let the recipient know that another system ("us") was involved in the mailing. Here is an example of Gmail showing an email where "via..." is added next to the From email.

If you don't want these messages to appear, authenticate using your own domain or disable automatic authentication for domains missing SPF and/or DKIM authentication in Settings > Account settings > Deliverability Checkup > Authentication. However, we strongly recommend keeping it on for better deliverability.

Why it matters

The importance of DKIM authentication is twofold:

It states that the authenticated domain did send the email
The contents were not modified by anyone during the transit

This is why it is considered the most robust email authentication method and it can increase your deliverability. That is: the percentage of your messages that are delivered to in the Inbox instead of the Spam folder.

Adding DKIM authentication

Adding DKIM authentication is easy. Here is what you need to do:

Contact your Web hosting company, domain registrar, or network administrator that manages this domain
Tell them that you need to make a change to the DNS (Domain Name System) records
Ask them to create the following two CNAMEs (replace "mydomain.com" with your domain)
```
(1) ml01._domainkey.mydomain.com 
```

... and point it to

ml01.dkim.musvc.com.

(2) ml02._domainkey.mydomain.com

... and point it to
```
ml02.dkim.musvc.com.
```

If a CNAME cannot be created, you may also establish DKIM authentication by adding the following TXT records to the DNS settings. Please contact us for additional details

Wait 24-48 hours: it takes a bit of time to changes to propagate around the Internet
Run this test again to confirm that the CNAMEs have been successfully updated.