> For the complete documentation index, see [llms.txt](https://docs.aurelia.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.aurelia.io/developer-guides/error-messages/router/aur3401.md).

# AUR3401

## Error Message

`AUR3401: Neither the route '%s' matched any configured route at '%s' nor a fallback is configured for the viewport '%s' - did you forget to add '%s' to the routes list of the route decorator of '%s'?`

## Description

This error occurs when the router cannot recognize the requested route and there is no fallback configured for the target viewport.

## Common Scenarios

* Navigating to a path that is not configured in the route table.
* Forgetting to register a routed component (or its routes) in the correct routing context.

## Solutions

* Add the missing route to your route configuration.
* Ensure the component that owns the routes is registered/active for the current navigation.
* Configure a fallback route for the viewport if desired.

## Troubleshooting

* Check the path you are navigating to and compare it with configured routes.
* Verify the component mentioned in the last `%s` has the route configured.


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