> For the complete documentation index, see [llms.txt](https://docs.emaildelivery.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.emaildelivery.com/docs/common-email-setup-issues/unconfigured-sending-domain-during-test-message.md).

# "Unconfigured sending domain" during test message

{% hint style="info" %}
**Your sending domain must match the authenticated domain in your ESP account perfectly, including any subdomain.**
{% endhint %}

<figure><img src="https://2024949584-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FHNgw7cfnOYHQr0B6GDXr%2Fuploads%2FGI9es2BQdzhk3IIqsr9I%2FScreenshot%202023-10-29%20at%204.06.33%E2%80%AFAM.png?alt=media&amp;token=519892c2-21b1-40a6-ab02-8b69df2c5057" alt=""><figcaption></figcaption></figure>

<figure><img src="https://2024949584-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FHNgw7cfnOYHQr0B6GDXr%2Fuploads%2F1Z5r2b3YXCkzhrLnh7O3%2FScreenshot%202023-10-29%20at%204.09.23%E2%80%AFAM.png?alt=media&amp;token=54f1db68-c87d-41b7-92d2-76a73fb4f3f8" alt=""><figcaption></figcaption></figure>