Before connecting Sage Intacct, a few things need to be set up on both sides. This guide lists them, along with what isn't supported.
The full guide covers:
Enabling Web Services and creating a Web Services user
Authorizing the Alvys sender ID
Alvys subsidiaries and external account IDs
Features that aren't supported
Also known as: Sage Intacct setup, Web Services, sender ID, Intacct prerequisites.