# E04038 — EmailTemplateVersionNotPublished

You can only roll back to a published version.

- **HTTP status**: `422`
- **Type**: `validation_error`
- **Name**: `EmailTemplateVersionNotPublished`

## What to do

The version you named is not published, so it cannot be rolled back to. List the template's versions to see which ones are published, then roll back to one of those.

## Related

- [E04xxx — Email sending & delivery](/docs/api/errors/E04xxx): every code in this range
- [Errors](/docs/api/errors): the full wire contract, status mapping, and error catalog
- [Error handling](/docs/guides/errors): branching on `type` and `code`, validation details, and `vendor_code`

## Related resources

- [Should I use a Bird SDK or call the API directly?](/explained/platform/should-i-use-an-sdk-or-call-the-api-directly) (answer)
- [Build your first integration](/learn/paths/integration) (course)
- [Send your first email](/docs/get-started/send-your-first-email) (docs)

[Get an implementation brief](/learn/workspace?topic=api-basics)