This article covers the SPF and DKIM configuration process for Customer.io and how they are managed in Valimail. Because this service leverages Mailgun's email infrastructure, it requires additions to your DNS records outside of the Valimail platform. Adding Customer.io as an authorized sender in the Valimail platform usually requires a dedicated subdomain to be pointed to the Customer.io infrastructure and typically the DKIM keys will be added in the Valimail platform.

You must set up at least one sending domain before you can send emails from your Customer.io workspace.

1. Go to Settings -> Workspace Settings.

2. Click Email Settings and then click Add Sending Domain.

3. Enter the Domain, Display Name, and Email Address that you want to send messages from, and click Add Domain.

4. Follow the Workspace Settings link in the left-hand menu in your Customer.io account, choose Email from the list of message types and then select the Sending Domains tab.

5. Click the Verify domain button for the domain you would like to authenticate. This is where you will see the MX records that need to be added in your DNS and DKIM records that you need to add in Valimail Enforce in order to authenticate your domain.

6. Please add the MX records in your domain's DNS and the DKIM key in Valimail Enforce. You will also need to add Customer.io in your Enabled Senders list in Enforce, which accounts for adding the Customer.io's SPF include in your SPF record.

7. After you are finished with adding the records in DNS and Valimail Enforce, you will need to come back to the Deliverability page and click the Verify domain button. We will then check that the records and values are correctly in place. If all three records are verified by green checkmarks, then your domain is verified and you’re all set to start sending from that domain.

You can also find the instructions on how to set up DKIM and SPF for Customer.io here.

You can find more detailed information on how to add a DKIM key in Valimail, here:

Once you establish that Customer.io is an authorized sender for your domain, you will need to add the service in your Enabled Senders.

You will find more detailed information on how to add a service for your domain in Valimail, here:

Note: We encourage you to use the comment section for any useful information about your sending service, such as the name of the service owner, change request ticket numbers, etc.