Retrieve data from an external source

Hi Wingmen ,

Thanks for reaching out to Microsoft Fabric Community.

I understand the confusion, especially since the API works in the browser and Power BI Service but not in Power BI Desktop.

Power BI Desktop does not support client certificate based authentication for API calls, so it cannot directly use .pfx, .pem, or similar certificate files when calling an endpoint. Because of this, the behavior you are seeing in Desktop is expected.

Solved: Issues using a Web Certificate to authenticate API... - Microsoft Fabric Community

From an ease and security perspective, one option is to check with the API provider whether they can expose a token based authentication method such as OAuth2 or bearer tokens, which are fully supported in Power BI Desktop.

Power Query Web connector - Power Query | Microsoft Learn

Solved: How to pull data from Web API into PowerBI using A... - Microsoft Fabric Community

If certificate based authentication cannot be changed, another approach is to introduce an intermediate service such as Azure Function or Azure API Management. In this model, the intermediate service handles the client certificate and mutual TLS, while Power BI connects using a standard HTTPS endpoint with supported authentication.

Secure APIs using client certificate authentication in API Management - Azure API Management | Microsoft Learn

A custom connector can also solve this, as mentioned earlier, but it requires additional development and ongoing maintenance, so it is typically considered when the authentication method cannot be changed.

Develop a connector using the Power Query SDK - Power Query | Microsoft Learn

Hope this helps you decide on the safest and most practical approach for your setup.

Thank you.