Forum Discussion
We encountered an unexpected error - Power BI Service Dataflow
This has noithing to do with too long exception. This is no exception. Just a Session ID and the above error message.
Look at the comment section of your Blog. Another user also reported about August Gateway update causing this error:
https://powerbi.microsoft.com/en-us/blog/on-premises-data-gateway-august-2021-update-is-now-available/
Super UserOuch. Dataflows is not very friendly with messages. You can do two workarounds.
1- Refresh the data inside the Dataflow transform data tool and check if something comes up. If everything is ok, try sorting all tables by a column (usually sorting will let the engine check for each value to bring on the top 1000 rows that it's showing and there might be an error on a row that's not the first 1000)
2- If you can't find the error there. You can always copy the table or code (from advanced editor) to a power bi desktop file transform data menu. The Desktop app is way more friendly with error messages. The close & apply will explain the issue.
I hope one of those help you.