Assume that you install SQL Server 2016 Reporting Services in SharePoint mode and you add a new data source of type Microsoft SharePoint List. You save the new data source without problem. However, when you click the Test Connection button, you receive an error message that resembles the following:
The connection string is not valid. ---> Microsoft.ReportingServices.DataExtensions.SharePointList.SPDPException: The connection string is not valid.
When you use the data source in a Reporting Services report, you receive the following error message:
The connection string is not valid.
Additionally, an error message that resembles the following is logged in the Reporting Services log file:
w3wp!processing!f!date time:: e ERROR: Throwing Microsoft.ReportingServices.ReportProcessing.ProcessingAbortedException: [AbnormalTermination:ReportProcessing], Microsoft.ReportingServices.ReportProcessing.ProcessingAbortedException: An error has occurred during report processing. ---> Microsoft.ReportingServices.DataExtensions.SharePointList.SPDPException: The connection string is not valid.
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