[BUG] Dataflow Gen2 destination picker 404 — api.powerbi.com lakehouses UK region
Hi community, We have a complete blocker with Dataflow Gen2 (CI/CD) destination configuration in our UK-region Fabric tenant. The Error: When clicking "Add default destination" and selecting a Fabric Lakehouse from the OneLake catalog, this error fires immediately for ALL users including the workspace Admin: DataSource.Error: Downstream service call to url 'https://api.powerbi.com/v1/workspaces/{WORKSPACE_ID}/lakehouses' failed with status code 404. (Region: uk) The Lakehouse IS visible in the OneLake catalog — it appears in the picker. The 404 fires the moment it is clicked. Root cause hypothesis: The destination picker calls the legacy Power BI REST API: api.powerbi.com/v1/workspaces/{id}/lakehouses ← returns 404 For Fabric-native workspaces in the UK region, the correct endpoint should be: api.fabric.microsoft.com/v1/workspaces/{id}/lakehouses The OneLake catalog listing (which uses a different path) resolves the lakehouse correctly — it's only the destination configuration call that uses the wrong endpoint. Workarounds attempted — all failed: 1. UI — Admin user attempted same steps → same 404 2. queryMetadata.json via Git — Added destination fields, pushed to prod branch → Fabric silently strips loadEnabled/destination on every sync, creating a permanent conflict loop (workspace ≠ Git on every update) 3. Authentication methods — Before the error began firing immediately, a "Connect to default data destination" screen appeared offering two authentication options for the Lakehouse connection: - Organizational account (Sahil Singh / user account) - Service principal Both were attempted. Neither succeeded — the 404 followed in both cases. Subsequently, this connection credentials screen stopped appearing altogether. The 404 now fires immediately upon clicking lh_dhl_prod in the OneLake catalog, before the connection setup dialog is even shown. This regression suggests the failure point has moved earlier in the destination configuration flow. Questions: 1. Is this a known issue for UK-region tenants? 2. Is there a way to configure the Dataflow Gen2 destination via Fabric REST API directly to bypass the broken UI? 3. Are there other file-based approaches (mashup.pq metadata) for CI/CD Dataflow Gen2 destinations? Happy to provide Session IDs and further details to the Fabric team. I have attached the relevant images, PFA... Thanks
Dataflow Gen2 - failing to load into the lakehouse
Hello. I have a dataflow gen2, fetching data from an azure data factory environment and loading them into a Fabric Lakehouse. It has been working flawlessfly for the last 3 months, but since two weeks, on some of the tables, I get this error: "There was a problem refreshing the dataflow: "Something went wrong, please try again later. If the error persists, please contact support.". Error code: EntityUserFailure. (Request ID: 6d111afc-11ee-459f-9e31-db4d08c32c44)." "XXX - ABC Entity Management_WriteToDataDestination: There was a problem refreshing the dataflow: "Couldn't refresh the entity because of an issue with the mashup document MashupException.Error: Error in creating lakehouse table in a version, InnerException: Tables can only contain uppercase or lowercase letters, numbers or the underscore character., Underlying error: Tables can only contain uppercase or lowercase letters, numbers or the underscore character. Details: Reason = Expression.Error;ErrorCode = Lakehouse036;Message = Tables can only contain uppercase or lowercase letters, numbers or the underscore character.;Message.Format = Tables can only contain uppercase or lowercase letters, numbers or the underscore character.;ErrorCode = Lakehouse019;InnerErrorCode = Lakehouse021,Lakehouse019;Microsoft.Data.Mashup.Error.Context = User GatewayObjectId: 1ee1c1a1-a11v-32bt-a19b-5ff6d874f432". Error code: 104100. (Request ID: 66d111afc-11ee-459f-9e31-db4d08c32c44)." The weird part is that there is no consistency between which tables go to error and which ones proceed to being loaded. Sometimes it works sometimes it does not. Also, there are no issue with the naming, as all the columns are respecting the requirements laid out from the error. And above all, it was working flawlessly until few weeks ago and nothing a
Dataflow Gen2 Copying Old Data
I have a dataflow that is transforming data and then moving it to a staging table in a Silver Lakehouse. I keep having issues where the number of rows moved to that lakehouse doesnt match what I am seeing in the dataflow preview or what it should be. A simple example of this is that this should have read 2 and written 2 rows but instead it read and wrote 3 rows. Upon investigating this was the 3 rows from the previos time it ran, suggesting a caching issue! I have others where I have 578 new rows in my table within the dataflow and then in the Staging table it has 212 rows. I'm very confused as to what is going on and concerned I may need to convert to notebooks for my transformations?
