1. In Sales or Service Cloud, navigate to the Marketing Cloud tab.
2. Click Configure Marketing Cloud Connector.
3. Click Manage Business Units.
4. Confirm that previously active Business Units are still active.
5. If Marketing Cloud Connect API user credentials did not migrate, click Change API User from the configuration page.
6. Enter the Marketing Cloud Connect API user credentials and save.
7. Click Manage Business Units.
8. Confirm that previously active Business Units are now active.