Microsoft Graph Sharepoint list item returning error 'Unsupported extension property type from backend.'

Gavin How 0 Reputation points

Trying to find the column values for a SharePoint list item; Example URL:<site-id>/lists/<list-id>/items/<item-id>?expand=fields&select=id,fields Getting a malformed JSON response of

"id": "64006"{
        "error": {
            "code": "InternalServerError",
            "message": "Unsupported extension property type from backend.",
            "innerError": {
                "date": "2023-04-05T17:51:51",
                "request-id": "<id redacted>",
                "client-request-id": "<id redacted>"

I've tried searching the web for some pointers but don't seem to be many people with this issue. Any help would be appreciated cheers.

Microsoft Graph
Microsoft Graph
A Microsoft programmability model that exposes REST APIs and client libraries to access data on Microsoft 365 services.
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A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
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  1. HarmeetSingh7172 4,811 Reputation points

    Hello Gavin How, Thanks for reaching out! The error message suggests that there might be an issue with one of the extension properties in your SharePoint list item. Extension properties are custom properties that are added to list items. In case you have recently made any changes to your SharePoint list schema, try rolling back those changes to see if issue goes away. Since, I'm not able to replicate this error message which you are getting, and API is returning results as expected for me, so I would suggest you raise a support case with Microsoft Graph, a Support Engineer will be able to assist you better. You can raise support ticket from or Hope this helps. If the answer is helpful, please click Accept Answer and kindly upvote. If you have any further questions about this answer, please click Comment.