# AUR3172

## Error Message

`AUR3172: RouteContext has no ViewportAgent: %s`

## Description

This error occurs when the router expects a `ViewportAgent` to exist for a `RouteContext`, but none can be resolved. This can indicate a misconfigured viewport setup or an internal state issue.

## Solutions

* Ensure your routed view has the expected viewport configuration.
* Ensure the router has been started and is operating within a valid routed component tree.

## Troubleshooting

* If this occurs without custom router integrations, please report it with a reproduction.


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