Cannot create Notebook connection with Workspace Identity authentication

[apturlov]

I wanted to create a Notebook connection for a Notebook activity in Factory pipelines using Workspace Identity instead of Service Principal but encountered an error. I am aware that this feature may not be completely rolled out but I would not expect it to be available in Fabric UI if it's not available in my region. As it happens now, both Fabric documentation and Fabric UI allow choosing a Workspace Identity to be used for authentication in Notebook connection, but creating one is impossible.

UI shows an error:

This error is corresponding to an API request, as seen in the browser:

Very confusing, that the response is 200 OK, but the response content clearly shows that something went wrong:

The powerBIApiErrorObject has this content:

{
    "Code": "DMTS_InvalidCredentialTypeError",
    "Message": null,
    "Target": null,
    "Details": null,
    "InnerError": null,
    "pbi.error": {
        "code": "DMTS_InvalidCredentialTypeError",
        "parameters": {},
        "Details": [],
        "ExceptionCulprit": 1
    }
}

 I wonder if anyone has better insights in this situation and can explain.

[Olufemi7 · Accepted solution]

Hello @apturlov, 

You’re seeing the DMTS_InvalidCredentialTypeError because Notebook connections in pipelines don’t yet support Workspace Identity authentication, even though the Fabric UI currently shows it as an option.

The backend rejects this credential type, which is why the API call returns 200 OK but includes the error object.

At the moment, the only supported authentication method for Notebook connections in pipelines is Service Principal. Workspace Identity support is planned and has started rolling out, but it isn’t fully enabled yet — so this isn’t a regional issue or a misconfiguration on your side.

For reference:

• Microsoft Learn – Authenticate with Workspace Identity 

  • Explains where Workspace Identity can be used. Notebook pipeline connections are not yet listed as supported.

  • Microsoft Fabric Blog – Run Notebooks in Pipelines with Service Principal or Workspace Identity  (Connie Xu, Dec 2025) confirms that Workspace Identity support for Notebook activity in pipelines is rolling out gradually and is expected to be fully available by early 2026.

  So for now, if you need to proceed, you’ll need to configure the connection with a Service Principal until Workspace Identity becomes generally available.

[v-menakakota]

Hi @apturlov ,

Thanks for reaching out to the Microsoft fabric community forum. 

This is a current product limitation.  Even though the Fabric UI shows Workspace Identity as an option for Notebook connections, the backend does not yet support it, which results in the DMTS_InvalidCredentialTypeError. It’s not a region or configuration issue.

For now, Service Principal is the only supported authentication for Notebook connections in pipelines.

If I misunderstand your needs or you still have problems on it, please feel free to let us know. 

Best Regards, 
Community Support Team