> 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/aur0767.md).

# AUR0767

## Error Message

`AUR0767: Aurelia.root was accessed without a valid root.`

## Description

The `root` property needs either a current application root or one configured for the next start. Calling `app(...)` creates that configuration. The property is available immediately and remains available throughout startup.

This state commonly occurs on a fresh `Aurelia` instance or after `stop(true)` disposed the configured root.

## Solution

Configure the root before reading it:

```typescript
import Aurelia from 'aurelia';
import { MyApp } from './my-app';

const aurelia = new Aurelia().app({
  host: document.querySelector<HTMLElement>('#app')!,
  component: MyApp,
});

const root = aurelia.root;
await aurelia.start();
```

Call `app(...)` again before a later start when the previous root was disposed.


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