Error embedding fabric dashboard

Hi, Syndicate_Admin 

According to your description,401 error usually indicates an unauthorized request, which can be due to a number of reasons. You can check the following points.

1. Ensure that the service body has been correctly added to the workspace to be enabled.
powerbi - Unauthorized (401) Power BI Embedded using the samples Node and .NET - Stack Overflow

2. Ensure that the workspace and its underlying dataset are not in My Workspace. If the dataset is in My Workspace, try moving it to another workspace.
javascript - 401 Unauthorized error when trying to generate an embed token for PowerBI report - Stack Overflow

3. Error debugging, you can also add an error event listener to the embedded code or use a tool such as Fiddler to monitor HTTP traffic and find out more details about the error may be helpful.

How to troubleshoot and debug your embedding code in Power BI embedded analytics | Microsoft Learn
Troubleshoot Power BI embedded analytics application - Power BI | Microsoft Learn

Best Regards,
Yang
Community Support Team

If there is any post helps, then please consider Accept it as the solution to help the other members find it more quickly.
If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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I've validated the suggestions but haven't been able to make it work.

The Fabric Workspace in which I want to enable embedding doesn't have the option from POWER BI to include users (in the previous one I could).

As I understand it, that should be done by office365 group management. I've already included the same user I used previously in the Power BI worspace.

Even so, you still get a 401 error when requesting the dashboard access token.