To authenticate a Constant Contact a connector instance, you must register an app with Constant Contact and know the API Key, API Secret, and Callback URL of the app.

To register an app:

1. Log in to the Constant Contact Constant Contact Mashery page.
2. Follow the steps provided to register your app.
3. Record the Key and Secret. When you authenticate a connector instance, use Key as the apiKey and Secret as the apiSecret.
4. Click the my account link below the API information or click the Apps & API Keys tab.
5. Click Applications under My API Keys, find your app, and then click Edit.
6. In Redirect URI for OAuth calls, enter the Callback URL where the user returns after authentication. Enter this URL whenever prompted to enter a Callback URL when you authenticate an a connector instance.
7. Click Save.