Dataflow error messages are completely worthless.

Hi , paulmadison 

As far as I know, if you encounter an error in the PQO step of the data stream, you can navigate to the corresponding step that encounters the error and view the detailed error information corresponding to the encounter, if you encounter the error message when saving the data stream or refreshing the data stream, for the public user can only see a brief error message, if you want to get more detailed instructions, you need to expand the error detail and provide us with Power BI's technical support to query the internal database and give you the corresponding error insights, I think this is for Microsoft's security and data privacy considerations, because the query of the internal database permissions for us will also expire regularly and need to be updated regularly.

For troubleshooting and analysis of data flow issues, you can first refer to the guidelines of the official documentation of PBI:

Troubleshooting dataflow issue - get data from dataflow - Power Query | Microsoft Learn

Best Regards,

Aniya Zhang

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