Gateway Data MashUp error

[FODK]

Hi,

I am dealing with the following problem with 3 of the reports I run (out of +-90):

We are using an on-prem SQL server and this (and the other two problem giving reports) have an excel file stored on sharepoint connected, through a cloud connection; all are online -> 

What would be possible avenues to look into? We can run the refresh in Desktop manually.

Connection errors doesn't seem the case, Gateway error seems unlikely as well as firewall problems; all is online and other reports with same set-up are running fine

[rohit1991 · Accepted solution]

Hi @FODK ,
You're encountering a refresh failure in a few specific reports that use a SharePoint-hosted Excel file as a data source, in addition to an on-prem SQL Server, and the issue appears to stem from the Power BI Gateway not handling the SharePoint connection properly. Even though the SharePoint file is online and accessible, the error message points to a MashupDataAccessError, which typically indicates a problem with how the gateway tries to combine on-prem and cloud sources — known as hybrid data source limitations. 

The fact that the refresh works in Power BI Desktop (where credentials and access context differ) but fails via the service suggests that the gateway is either not authorized to access the SharePoint file or is not correctly mapped to a supported connector. Check that the gateway data source mappings align exactly with the connection paths used in the report, and that the SharePoint source is using a cloud connection properly mapped to a certified data source (e.g., Organizational account). You may also want to avoid combining on-prem and cloud sources in the same query unless absolutely necessary, as that often triggers privacy level and mashup engine limitations.