API Settings
You can reach the plugin settings by choosing the WooCommerce → Settings → Shipping → Australia Post Live Rates from the sidebar.
In order to offer your customers the available Australia Post services based on the order details and display them in the cart and checkout, you need to enter an API Key for the PAC and Postcode Search in the plugin settings.
If you do not have an API key for the Postage Assessment Calculator yet, check how to get the API access key →.

API Connection Status
– once your login credentials were entered and Save changes button hit, the API Connection Status should change to OK and turn green.

If for some reason, the plugin is not able to establish the connection with the Australia Post API, you will see the error message coming from the API with the detailed information on the cause of the problem.