Forum Discussion
Dataverse table access fails with TDS error 8657 in Fabric Dataflow
Hi everyone,
I’m experiencing an issue with the msdyn_project table when connecting to Dataverse from Microsoft Fabric Dataflow Gen2.
This is part of an existing production data pipeline that has been running on a scheduled refresh for several months.
Background
The existing pipeline has generally been working successfully. From time to time, we have experienced intermittent User Identity Failure during scheduled runs, but those failures have typically recovered automatically on a subsequent refresh.
I am now making an update to the solution because I need to bring additional data into the Lakehouse, Semantic Model, and Power BI report.
During testing, I created a new Dataflow Gen2 to connect to the same Dataverse environment. I can access and preview other Dataverse tables successfully, but I cannot preview the msdyn_project table.
Error
When I select msdyn_project, I receive:
The service has encountered an error processing your request. Please try again. Error code 8657. A severe error occurred on the current command. The results, if any, should be discarded.
Additional error details:
DataSourceKind = CommonDataService ErrorCode = 10478 Number = 40001 Class = 16 State = 1
Troubleshooting
I have confirmed the following:
- The existing Dataflow has been running successfully on a schedule for months.
- The Dataverse connection is working.
- Other Dataverse tables can be opened and previewed successfully.
- I created a new Dataflow Gen2 and reproduced the issue.
- The issue occurs specifically with msdyn_project.
- The error occurs when attempting to preview the source, before applying any Power Query transformations.
- Therefore, the issue does not appear to be related to my existing M code, Lakehouse destination, Semantic Model, or Power BI report.
Has anyone encountered Dataverse TDS error 8657 / 40001 specifically when accessing msdyn_project through Microsoft Fabric?
I’m looking for recommendations on how to diagnose the issue and determine whether a specific field, metadata change, or service-side issue is causing the failure.
Thank you!
The issue has been resolved with a workaround. I split the source query into two smaller queries and then joined them back together, keeping the existing final table structure unchanged. This avoids the TDS connector error caused by the large number of columns in the project table.
The data is now refreshing successfully.
Microsoft still needs to investigate and resolve the underlying Dataverse connector/TDS issue because I am still unable to preview the data through the normal Dataverse connector.
4 Replies
Update: The Project table issue has been resolved with a workaround. I split the source query into two smaller queries and then joined them back together, keeping the existing final table structure unchanged. This avoids the TDS connector error caused by the large number of columns in the project table.
Microsoft still needs to investigate and resolve the underlying Dataverse connector/TDS issue because I am still unable to preview the table data through the normal Dataverse connector. The Azure team has submitted a Microsoft Support ticket and will update us when they receive feedback from Microsoft.
The issue has been resolved with a workaround. I split the source query into two smaller queries and then joined them back together, keeping the existing final table structure unchanged. This avoids the TDS connector error caused by the large number of columns in the project table.
The data is now refreshing successfully.
Microsoft still needs to investigate and resolve the underlying Dataverse connector/TDS issue because I am still unable to preview the data through the normal Dataverse connector.
Because other tables work and a new Dataflow reproduces the failure before transformations, investigate the msdyn_project source query separately from the Lakehouse or semantic model. Connect to the same Dataverse TDS endpoint in SQL Server Management Studio using the same authorized identity. Test a TOP 10 query selecting only the table's primary-key column, then add required columns in small groups. Microsoft recommends limiting rows and columns; choice labels and large text columns can make these queries more expensive. If the minimal query succeeds, compare it with the Dataflow query and test disabling relationship columns through CreateNavigationProperties=false in a separate test query. That option addresses documented metadata overhead, not a confirmed fix for error 8657. If even the minimal query fails, retain its exact text, UTC timestamp, request identifier, and error details for Dataverse support. Do not change production metadata based on this error alone.
Hi Jamony,
Thank you for your response, I am not able to preview the data at all, even in a brand-new Dataflow with no transformations. Since other Dataverse tables work and this failure occurs before transformations, Lakehouse loading, or the semantic model, this points to a Dataverse connector/TDS issue.
