> 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/aur3271.md).

# AUR3271

## Message

`AUR3271: Transition %s failed with error: %s`

## Description

This error is logged when a router transition fails due to an exception during navigation.

## Common Scenarios

* An exception thrown from a lifecycle hook (`canLoad`, `loading`, `canUnload`, etc.).
* An exception thrown while resolving a component/view-model.
* A custom navigation strategy throws.

## Troubleshooting

* Inspect the second `%s` value (the original error) for the root cause and stack trace.
* If the failure comes from a hook, add logging inside the hook to confirm inputs and return values.


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