> 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/0203-to-0227/aur0217.md).

# AUR0217

## Error Message

`AUR0217: There is no registration for IDirtyChecker interface. If you want to use your own dirty checker, make sure you register it.`

## Description

This error occurs when Aurelia needs to use dirty checking but cannot resolve an `IDirtyChecker` implementation from the container.

## Common Scenarios

* A custom build/configuration removes or replaces the default dirty checker without registering a replacement.
* You explicitly enabled a feature that relies on dirty checking but didn’t register a dirty checker.

## Solutions

* Ensure the default dirty checker is available (standard runtime setup).
* If you provide a custom dirty checker, register it with the container.

## Troubleshooting

* Verify your app startup/DI registrations include an `IDirtyChecker` implementation.
* If you use a custom platform/runtime bundle, confirm it did not exclude dirty checking support.


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