---
title: "NUXT_E2004"
description: "Unknown route middleware."
canonical_url: "https://nuxt.com/docs/4.x/errors/e2004"
---
# E2004

A route middleware was referenced (usually via `definePageMeta({ middleware: [...] })`) but no middleware with that name exists. Common causes are a typo in the name, or a middleware file that was renamed or deleted without updating its references.

## Resolution

Make sure the name matches a file in `middleware/`. Names are derived from the filename: `middleware/auth.ts` is referenced as `auth`.

<read-more to="https://nuxt.com/docs/4.x/guide/directory-structure/middleware">



</read-more>


## Sitemap

See the full [sitemap](https://nuxt.com/sitemap.md) for all pages.