When attempting an authorization request, the service provider or relying party displays the following error message:

The response type is not supported by the authorization server. Configured response types: [code, id_token]

• OAuth 2.0
• OpenID Connect (OIDC)
• Okta Applications (General Settings)
• Custom Authorization Servers (Access Policies)

This issue occurs because the specific grant type required for the OAuth/OIDC flow being used is not enabled in the Okta application's General Settings or within the Access Policies of a Custom Authorization Server. The response_type parameter in the authorization request does not align with the configured grant types on the Okta side.

1. Enable the required Grant Type in Okta Application Settings:

   1. Access the Okta Admin Console.

   2. Navigate to the application.

   3. Go to the General Settings tab.

   4. Under General Settings, locate the "Grant type" section and enable the grant type corresponding to the OAuth/OIDC flow where the service provider/relying party is implementing (for example, "Authorization Code," "Implicit," "Hybrid").

   
    
   
   

   2. Enable Grant Type in Custom Authorization Server Access Policies (if applicable):

   1. If using a Custom Authorization Server, navigate to Security > API in the Okta Admin Console.

   2. Select the Custom Authorization Server.

   3. Go to the Access Policies tab.

   4. Select the relevant policy and Edit Rule.

   5. Ensure the necessary grant type is enabled within the policy rule.

   
    

3. Verify response_type in the Application's Authorization Request:

• After configuring the settings in Okta, confirm that the application is passing the correct response_type value(s) in its authorization request, matching the enabled grant types.
  For example:

  • For Authorization Code Flow, use response_type=code.

  • For Implicit Flow, use response_type=id_token or response_type=token id_token.

  • For Hybrid Flow, use response_type=code id_token.

Related References

• Request Parameters - Okta Developer Documentation

• Grant Types - Okta Developer Documentation