Setting up DKIM for Zendesk will help emails pass DMARC alignment and another key benefit that you will experience is improving your domain reputation among ISPs that will ensure fewer chances of your emails being marked as spam.
Create Custom Domain for DKIM on Zendesk
1. Log in to your Zendesk account.
2. Navigate to Admin > Channels >Email
3. Navigate to Custom domain for DKIM. Here you will find 2 CNAME records to be added to Valimail Enforce for selectors zendesk1 and zendesk2
4. The two CNAME records would appear as zendesk1._domainkey.yourdomain.com pointing to zendesk1._domainkey.zendesk.com and zendesk2._domainkey.yourdomain.com pointing to zendesk2._domainkey.zendesk.com (The record values are the ones bolded).
5. Go to your domain's Configuration page in Valimail Enforce and publish the newly created Zendesk DKIM keys.
a. Click on Add a DKIM key and fill in the info from the newly created Zendesk keys and then click Add.
Note: When you add Zendesk to your Enabled Senders list in Valimail Enforce, 2 default Zendesk DKIM keys will be usually added in the DKIM management section in Enforce. If that will be the case, please delete them and proceed to add the 2 DKIM keys issued in the Zendesk console for your domain as described above.
6. After the records are published in Valimail Enforce, head back to Zendesk and simple click on Enable checkbox in the Custom domain for DKIM section.
7. Click on Save to create your custom domain for DKIM on Zendesk
8. Once the Zendesk DKIM keys are enabled, you are ready to sent DKIM authenticated emails for your domain using Zendesk.