> 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/runtime-html/aur0505.md). # AUR0505 ## Error Message `AUR0505: Controller at is in an unexpected state: during deactivation.` ## Description Aurelia found a controller state outside the supported deactivation transitions. Repeating a deactivation already in progress returns its current result, and deactivating an inactive controller completes immediately. A deactivation requested during activation stops later activation phases before teardown proceeds. Check any integration code that controls the controller lifecycle directly. It may have changed `controller.state` or called a controller method outside its lifecycle contract. If this occurs through standard routing or template composition, capture a minimal reproduction for the Aurelia team. ## What to Check * Find direct writes to `controller.state` and remove them. * Keep each low-level controller under one lifecycle owner. Await its current transition before starting unrelated work. * Record ``, ``, and the full stack trace. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.aurelia.io/developer-guides/error-messages/runtime-html/aur0505.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.