Unable to connect to Google BigQuery data source (August 2025 build)

[sparrow0hawk]

I am attempting to get data from Google BigQuery using the Get Data modal. After selecting "Google BigQuery" and clicking connect it opens a new modal for setting "Advanced options" if I leave these blank (as was possible in previous versions) and click OK I receive the following error:

We encountered an error while trying to connect:
Details: "ADBC: The service bigquery has thrown an exception. HttpStatusCode is Unauthorized. Request is missing required authentication credential. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project."

But there is no way to provide or request an authentication credential through the previous options. In previous versions you were provided an additional menu that allowed you to select Service Account Login or Organization login (as described in the docs) but it is now no longer possible to reach this menu.

Please can you confirm if there is another step I am missing or if this is a regression in the August 2025 build of PowerBI Desktop?

Feedback Type:
Frown (Error)

Timestamp:
2025-08-20T08:15:21.7805739Z

Local Time:
2025-08-20T09:15:21.7805739+01:00

Session ID:
9b9ee6d9-b3d5-4152-83ae-b35b5bb8bbe1

Release:
August 2025

Product Version:
2.146.705.0 (25.08)+b71502aff0a01340c88f384884ef42771068f115 (x64)

OS Version:
Microsoft Windows NT 10.0.19045.0 (x64 en-GB)

[shashiPaul1570_]

Hi @sparrow0hawk

The 401 “missing credential” error usually comes up because Desktop isn’t launching the Google OAuth prompt. A few things you can try:

• Go to Data source settings → Global permissions, clear any saved BigQuery/Google credentials.

• In Desktop Options, enable “Use my default web browser”, then retry so the OAuth login window opens properly.

• If your tenant requires it, set the Billing project under Advanced options.

• Alternatively, you can connect with a service account JSON (make sure the account has BigQuery Data Viewer + Job User roles).

• If none of that works in the August 2025 build, install the July 2025 Power BI Desktop as a temporary workaround — this looks like a regression in the new dialog.
  
  You can also find these links for more help
  https://stackoverflow.com/questions/79036379/power-bi-issue-refreshing-bigquery-data-sources-error-h... 

Google BigQuery (Microsoft Entra ID)

https://learn.microsoft.com/en-us/power-query/connectors/google-bigquery-aad 

Hope this helps resolve the issue! 👍
If it works, please don’t forget to give Kudos and mark this as Accepted Solution so others can benefit. ✅

Best Regards,
Shashi Paul 

[rohit1991 · Accepted solution]

Hi @sparrow0hawk 

This is the new BigQuery connector (ADBC, Preview) causing the odd auth flow. Two easy ways to unblock:

Quick fix (use the old flow):

• Power BI Desktop >> File >> Options >> Preview features >> uncheck “Use new Google BigQuery connector implementation” >> restart.

• Then Data Source Settings >> Clear Permissions and connect again you’ll get the old Organizational / Service Account sign-in screens.

If you stay on the new connector:

• Make sure you’re on 64-bit Desktop (required for the preview). 

• Connect again; you should see Organizational or Service Account sign-in. For service accounts, paste the JSON key as a single line (no line breaks) or it fails. 

If you still don’t get a sign-in prompt after that, clear credentials again and try the Google BigQuery (Microsoft Entra ID) connector for org login.

https://learn.microsoft.com/en-us/power-query/connectors/google-bigquery 
https://powerbi.microsoft.com/en-us/blog/power-bi-may-2025-feature-summary/?utm