RLS Access Error- but no intentional RLS set?

Hello,jzwanzig .Hi,AnalyticPulse ,thanks for your concern about this issue. 
Your answer is excellent.
And I would like to share some additional solutions below
I am gald to help you.

According to your description, you don't have RLS restrictions set in Power BI Desktop/Service, but the Viewer in worksapce accesses the report with "Access Denied . . becuase you don't have permissions to the underlying dataset".

Here is my analysis of this situation, you can refer to it:

1.RLS(Row-level-security) is a restriction for the dataset itself, so if you don't have any RLS settings on the desktop or service, if the dataset itself has RLS settings,(set RLS in the data source), then the filtered users still can't access the specific data, and can't view the report's content

Please check if RLS is set in the data source you are using.

For example, if you publish a report created using the model in Analysis Service as the original data to the service, and if you set the corresponding type of Role in the model, and set the corresponding RLS/OLS for different Roles, then the report will be restricted when the corresponding user accesses the report in the Power BI Service in the end. RLS/OLS is only available to Power BI Service users.

2. RLS is only valid for Viewer in workspace, but not for other types of users.

This solution does not seem to be suitable for you, because you need to set the user role as Viewer to protect the data security.

However, this also indirectly indicates that the problem may be caused by the RLS settings in the data source used by the report itself.

So I would suggest you to double check if RLS is set in Desktop or Service and then check if RLS/OLS is set in the datasource of the report itself.

If you are using SSMS (SQL SERVER Management Studio), you can use Sql Profiler for query tracing (or other tracing tools to query the backend), which will show you the role identity of the user who is accessing the data source, and the corresponding error type of denying the access to the data source (e.g. RLS).
URL: Dynamic row-level security with Analysis services tabular model - Power BI | Microsoft Learn

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.

Best Regards,

Carson Jian,

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.