If your ArcGIS Enterprise portal has CORS configured to restrict cross-domain requests to your portal, Power BI Desktop will not function as expected, as described in BUG-000133837.
If using ArcGIS Enterprise 10.7.1 or later, an administrator of your ArcGIS Enterprise organization can configure CORS to allow requests that originate from Power BI.
To add Power BI to the allowed origins, do the following:
Note: To complete this step, HTML access to the sharing API must be enabled. On many secured environments, HTML access to the sharing API is restricted. To enable HTML access to the sharing API, the disableServicesDirectory property under https://webadaptorhost.domain.com/webadaptorname/portaladmin/security/config must be set to false.
The Power BI origin is added to the allowed origins. The changes take effect immediately, without the need to restart the portal.