How to fix issues with custom tracking domains

In this article, you'll learn how to make sure your custom tracking domain works correctly—and the possible reasons it may fail.

Tracking domains with SSL

- Strengthen your sender reputation with providers, improving deliverability

- Enable HTTPS for all tracked links, making your emails look safer to spam filters

Snov.io automatically issues SSL certificates for custom tracking domains, so all tracked links use https, improving deliverability by making your emails appear safer to spam filters.

In some cases, a custom tracking domain cannot be added because of issues with your tracking domain settings.

How to check your custom tracking domain

Test in browser: Open the URL for your tracking domain or subdomain in your browser.

If the page loads in your browser over https, the certificate is active. If the page loads, then your domain is set up correctly. If it doesn’t, then there’s an issue with your setup.

To check if your SSL certificate works, open tracking domain URL from your email account settings in a browser. Use the format https://tracking-domain-URL.

Check DNS: Use any online DNS checker to verify your tracking domain. If all areas show green, then your domain is configured correctly. If they show red, then there’s a problem with your setup.

Make sure your DNS and CNAME records are configured correctly—if not, open and click tracking may fail.

Below are the possible issues and how to fix them.

Issue: Tracked links use HTTP

If tracked links in previously sent emails don’t load or use http instead of https, it means the tracking domain isn’t working correctly and Snov.io couldn’t generate an SSL certificate for it.

Without SSL, a custom tracking domain can’t use https to improve deliverability.

Reason 1: Your tracking domain URL contained an underscore (track._domain.com), which caused an error during SSL generation.

Fix: Check your tracking URL in CNAME record and make sure the format is correct. Remove any extra symbols if the address contains them.

Re-add the correct URL in the email account settings. We’ll verify it and automatically generate the SSL certificate.

If you have multiple senders that use the same tracking domain, you can edit them all at once using bulk-editing feature. Select the accounts that need adjustment and click Edit.

Reason 2: The domain on which the CNAME was created also has a CAA record that specifies which authorities can issue SSL certificates for it.

Fix: Go to your domain’s DNS and check the CAA record. If it exists, create a new one to include Snov.io’s SSL provider. Multiple CAA records can coexist on the same domain.

In CAA record, add this value: CAA 0 issue "sectigo.com".

This ensures Snovio is allowed to issue a certificate for your custom tracking domain.

Wait for DNS propagation (24–48 hours). Then re-add your tracking domain in Snov.io.

Issue: Tracked links from emails don’t load

Reason: If the CNAME record for the tracking domain you added to Snov.io is removed from your domain, the custom tracking domain will stop working.

Fix: Open your domain’s DNS settings and check the CNAME record. Update it or create a new one using our guide to ensure it’s set up correctly.

How to add or update CNAME record

To access the DNS settings, log in to your domain registrar (the provider where you purchased your domain) and find the DNS management section.

Step 1. Add a new CNAME record (type: CNAME or TXT). 

In the Points to or Value field: add Snovio’s URL: snov-stream.com. 

In the Name field, enter “track” or the full URL address in the format track.yourdomain.com.

The tracking domain URL shouldn’t contain any extra symbols, like _underscore.

Here's an example of how the CNAME record settings should look like:

Step 2. Add your tracking domain URL in the email account settings.

Before adding a tracking domain to Snovio, wait some time until your domain updates. DNS changes may take up to 24-72 hours.

Click Set up to start verification. We’ll check that everything works and generate the SSL certificate. Don’t forget to Save to apply your new settings.

Even with a custom tracking domain, open and click tracking in email campaigns can affect deliverability.

To minimize risks, warm up your custom tracking domain using the Email Warm-up tool.

Related articles:

How to warm-up custom tracking domain

How to set up custom tracking domain