The add-on works as a Connector between SAP Business One and Avalara, integrating the Avalara functionalities into SAP for tax calculations.

You have to configure the connection information at the Add-On Connection Setup.

Go To the Avatax->Settings->Connection Setup

Account Environment

Select to which environment you'd like to connect (Sandbox or Production)

Account Authentication

To authenticate against Avalara you need to provide your access credentials.
You can either use an Account login by using an Account Id and License key, or authenticate by user, providing your User name and password. Please select the authentication mode (By Account or By UserName) and fill in accordingly

Take in mind that each environment (Sandbox or Production) has its OWN credentials
This information is provided by Avalara. Please check with your Avalara Account Manager.

At this point, click in "Load Companies"
If the Account Environment matches the Account Authentication, the Company Code will be completed automatically. If you have multiple companies under the same account, you can select the correct company from the dropdown next to it.

Once done, click on "Update" to apply the connection and finally click on "Test Connection" to confirm the connection is successful

You can also check the following video showing the process described above