# E05000 — DomainAlreadyExists

A sending domain with this name is already registered in this workspace.

- **HTTP status**: `409`
- **Type**: `conflict_error`
- **Name**: `DomainAlreadyExists`

## What to do

This domain is already registered. Look it up and reuse or verify it instead of re-creating it.

Operations that resolve this:

- [List sending domains](/docs/api/reference/list-domains)
- [Get a sending domain](/docs/api/reference/get-domain)

## Related

- [Idempotency](/docs/api/idempotency): safe retries and key reuse rules
- [E05xxx — Domains & DNS](/docs/api/errors/E05xxx): 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`