Power BI Dataflow Cannot Authenticate Custom Connector with OAuth – "Path is invalid" Error

[SufiyanYousuf]

I'm using a custom Power BI connector (.mez) that connects to Microsoft Graph API using OAuth 2.0. The connector works perfectly in Power BI Desktop and also refreshes fine after publishing a report to the Power BI Service.

However, when I try to use this connector inside a Power BI Dataflow, I run into issues:

1. I choose Blank Query and enter:
   GraphAPIConnector.GetcallRecordsDetail()

2. When I try to configure the connection, it prompts me to create a new OAuth connection instead of using the existing one.

3. After signing in, I get this error:

"Unable to create an OAuth connection. Reason: Path is invalid:. Details: GraphAPIConnector (Session ID: , Region: europe)"

[v-pagayam-msft]

Hi @SufiyanYousuf ,
Could you please confirm if you've submitted this as an idea in the Ideas Forum? If so, sharing the link here would be helpful for other community members who may have similar feedback.
If we don’t hear back, we’ll go ahead and close this thread. For any further discussions or questions, please start a new thread in the Microsoft Fabric Community Forum we’ll be happy to assist.
Thank you for being part of the Microsoft Fabric Community.

[SufiyanYousuf]

Hi @v-pagayam-msft,
Sure, I will be submitting this as an idea in the Idea Forum as soon as possible, so it can be started as a new thread.

Thank you for your response.

Regards,

M.Sufiyan

[v-pagayam-msft · Accepted solution]

Hi @SufiyanYousuf ,

Thank you for the confirmation!
Please share the  submitted idea link after posting in the ideas forum. Sharing the link here would be helpful for other community members who may have similar feedback and upvote on it and accept your answer as solution to find it easily .

Regards,
Pallavi.

[Nasif_Azam]

Hey @SufiyanYousuf ,

You're encountering a known limitation when using custom connectors with OAuth authentication in Power BI Dataflows. While your custom .mez connector works perfectly in Power BI Desktop and refreshes in the Power BI Service, Power BI Dataflows (especially standard ones) do not support OAuth-based authentication for custom connectors.

Workaround 1. Use Dataflow Gen2 (in Microsoft Fabric)

If your environment supports Microsoft Fabric:

• Dataflow Gen2 has broader connector support and better OAuth integration.

• You can try moving your query into a Dataflow Gen2 and configure the OAuth there.

Requires premium capacity or Fabric license.

Workaround 2. Migrate Logic to Azure Data Factory or Power Automate

• Use Azure Data Factory (ADF) or Power Automate to extract data from Microsoft Graph API using the OAuth token and write it to a staging area (e.g., a Data Lake, Azure SQL, or SharePoint).

• Then connect Power BI Dataflow to the staging source.

Workaround 3. Use a Gateway with Anonymous or API Key Auth

• If you can rework your connector or service to expose a secured API with an API key or basic auth, you can avoid the OAuth issue altogether.

• Configure an On-Premises Data Gateway and use a web source with an API key or anonymous authentication in the Dataflow.

4. Pre-stage Graph Data Using Azure Function or Logic App

• Write an Azure Function or Logic App that pulls Graph API data using your OAuth connector and dumps the result into a storage location.

• Load this data into Power BI from the storage location (Blob Storage, Data Lake, etc.).

For Detailed Information:

Unable to create an OAuth connection. Reason: "Path is invalid" - GitHub Issue

OAuth custom connector - Microsoft Fabric Community

Handling authentication for Power Query connectors - Microsoft Learn

Verifying OAuth configuration for Custom Connectors - Microsoft Support

If you found this solution helpful, please consider accepting it and giving it a kudos (Like) it’s greatly appreciated and helps others find the solution more easily.

Best Regards,
Nasif Azam

[v-pagayam-msft]

Hi @SufiyanYousuf ,
Thank you for reaching out to us on Microsoft fabic Community Forum!

Upon my knowledge, Power Query Dataflows currently do not fully support custom connectors with OAuth authentication  even though they work fine in Power BI Desktop and Service.Please refer the link:Dataflows Limitations, restrictions and supported connectors and features - Power BI | Microsoft Lea... 

I would recommend posting the idea in the Power BI Ideas Forum .If there is already a post, please upvote on it too. Your input helps guide future improvements.

Thank you.

Regards,
Pallavi G.