Error when doing data refresh

Hi MirceaFlorea ,

You may go to File->Options and Settings->Data Source Settings->Global permissions in Power BI Desktop, find the data source stored SharePoint,  click "Edit permissions", then click "Edit", choose organizational account method (or Microsoft account) to sign in the appropriate credential.

or click "clear permissions" for stored SharePoint data source, then connect to the data using SharePoint folder connector again, use the URL below and use organizational account method.  See more: Connecting to Files in SharePoint & OneDrive with Power BI / Power Query.

https://xxxxx.sharepoint.com/sites/<sitename>

There is a similar case you may refer to: https://community.powerbi.com/t5/Power-Query/DataSource-Error-connecting-to-SharePoint-2010-list/td-p/23448.

Best Regards,

Amy 

Community Support Team _ Amy

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