Getting "407 Proxy," error in making API call to the AvaTax webservice
Overview
Environment
Online (Cloud) based proxy system
Resolution
When connecting to https://avatax.avalara.net via the AvaTax API, it checks for the proper certificates for security purposes on port 443.
When using an online (cloud) based proxy system, it will intercept the certificates on your behalf and pass along their certificate data to Avalara.
In order to allow AvaTax to reach its destination correctly, please call the online proxy provider and request that they not intercept your certificates to Avalara.