> 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.md).

# Router Errors

This section documents error codes emitted by [@aurelia/router](https://github.com/aurelia/aurelia/tree/master/packages/router).

## RouteContext / Router setup

* [AUR3155](/developer-guides/error-messages/router/aur3155.md) - RouteContext resolution failed
* [AUR3166](/developer-guides/error-messages/router/aur3166.md) - Eager path generation failed
* [AUR3167](/developer-guides/error-messages/router/aur3167.md) - No IAppRoot registered
* [AUR3168](/developer-guides/error-messages/router/aur3168.md) - Root RouteContext already registered
* [AUR3169](/developer-guides/error-messages/router/aur3169.md) - IAppRoot has no controller yet
* [AUR3170](/developer-guides/error-messages/router/aur3170.md) - Invalid context type
* [AUR3171](/developer-guides/error-messages/router/aur3171.md) - RouteContext has no RouteNode
* [AUR3172](/developer-guides/error-messages/router/aur3172.md) - RouteContext has no ViewportAgent
* [AUR3173](/developer-guides/error-messages/router/aur3173.md) - Lazy import requires path
* [AUR3174](/developer-guides/error-messages/router/aur3174.md) - No available ViewportAgent
* [AUR3175](/developer-guides/error-messages/router/aur3175.md) - Invalid lazy import component

## Router transitions

* [AUR3270](/developer-guides/error-messages/router/aur3270.md) - Scheduling next transition (trace)
* [AUR3271](/developer-guides/error-messages/router/aur3271.md) - Transition failed (error)
* [AUR3272](/developer-guides/error-messages/router/aur3272.md) - Root RouteContext not set

## Viewport agent

* [AUR3350](/developer-guides/error-messages/router/aur3350.md) - Unexpected activation
* [AUR3351](/developer-guides/error-messages/router/aur3351.md) - Unexpected deactivation
* [AUR3352](/developer-guides/error-messages/router/aur3352.md) - Unexpected state
* [AUR3353](/developer-guides/error-messages/router/aur3353.md) - Unexpected guardsResult

## Instructions / route resolution

* [AUR3400](/developer-guides/error-messages/router/aur3400.md) - Invalid component instruction
* [AUR3401](/developer-guides/error-messages/router/aur3401.md) - No matching route and no fallback
* [AUR3402](/developer-guides/error-messages/router/aur3402.md) - Unknown redirect route
* [AUR3403](/developer-guides/error-messages/router/aur3403.md) - Invalid instruction type for `toUrlComponent`
* [AUR3404](/developer-guides/error-messages/router/aur3404.md) - Incompatible instruction for eager path generation
* [AUR3450](/developer-guides/error-messages/router/aur3450.md) - No endpoint for path

## Route expression parsing

* [AUR3500](/developer-guides/error-messages/router/aur3500.md) - Unexpected segment
* [AUR3501](/developer-guides/error-messages/router/aur3501.md) - Unconsumed input
* [AUR3502](/developer-guides/error-messages/router/aur3502.md) - Unexpected expression kind

## Route configuration

* [AUR3550](/developer-guides/error-messages/router/aur3550.md) - Config from hook already applied
* [AUR3551](/developer-guides/error-messages/router/aur3551.md) - RouteContext required for component name
* [AUR3552](/developer-guides/error-messages/router/aur3552.md) - Component not found/registered
* [AUR3553](/developer-guides/error-messages/router/aur3553.md) - RouteContext required for lazy import
* [AUR3554](/developer-guides/error-messages/router/aur3554.md) - Invalid route config property type
* [AUR3555](/developer-guides/error-messages/router/aur3555.md) - Invalid route config type
* [AUR3556](/developer-guides/error-messages/router/aur3556.md) - Unknown route config property
* [AUR3557](/developer-guides/error-messages/router/aur3557.md) - Unknown redirect config property
* [AUR3558](/developer-guides/error-messages/router/aur3558.md) - Navigation strategy component not resolved


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