An Auth0 login implementation for an Ionic, Capacitor, and Angular application fails because the mobile operating system lacks the registered application identifier. Registering the application identifier on the operating system resolves the issue. The Ionic application displays an error message when it uses a callback URL in the format <appId>://<auth0Domain>/capacitor/<appId>/callback:

Failed to launch '{callbackUrl}' because the scheme does not have a registered handler

• Auth0
• Ionic
• Capacitor
• Angular

The mobile operating system lacks the registered application identifier and cannot recognize that the Ionic application handles the specific URL scheme.

What steps resolve the unregistered handler error?

To resolve the error, register the application identifier on the operating system and verify the configuration using the sample repository.

1. Register the application identifier on the operating system.

2. Verify the configuration using the Auth0 Ionic Samples repository.