# 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.
