# E04045 — EmailTemplateLanguageInvalid

The language is not a valid language tag.

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

## What to do

Give the language as a valid BCP-47 tag, for example 'en' or 'pt-BR'. This applies to the languages you save on a template as well as the language you name when sending.

## 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`