Power BI Desktop Data Refresh Error After September 2024 Update

Hi marianoalmeyda -Try re-entering your credentials in the data source settings:Go to File > Options and Settings > Data Source Settings.Find your SQL Server data source, and Clear Permissions.Reconnect to the server using the appropriate credentials.

You can enable diagnostic tracing in Power BI Desktop to get more detailed logs on what is causing the connection to fail:

Go to File > Options and Settings > Options > Diagnostics and enable Tracing.

After trying to refresh your data, check the logs for more detailed error messages in the Power BI Desktop\Traces folder.

Ensure that you’re running the 64-bit version of Power BI Desktop, as large datasets (200 MB or more) could face performance issues or connectivity failures in the 32-bit version.

Resource FYI

Troubleshoot refresh scenarios - Power BI | Microsoft Learn

Hope the above information helps.