OAuth requires the authenticating user to interact with Mailchimp using the browser. The driver facilitates this in various ways as described below.

Custom Credentials

You will need to register an app to obtain the OAuthClientId and OAuthClientSecret.

Web Applications

You need to create an OAuth app to use in the web flow.

Desktop Applications

You need to create an OAuth app.

Headless Machines

In the headless OAuth flow, users need to authenticate via a browser on another machine. You will need to create a custom OAuth app.

Creating a Custom OAuth App

See Creating a Custom OAuth App for a procedure.