I was getting this error in my ASP.NET application when I try to load a report into the report viewer control. To solve this I used the Reset() method of the report viewer control.



oReportViewer.Reset()
oReportViewer.ProcessingMode = Microsoft.Reporting.WebForms.ProcessingMode.Remote
oReportViewer.Visible = True
oReportViewer.ServerReport.ReportServerUrl = New System.Uri(sReportServiceURL)
oReportViewer.ServerReport.ReportPath = sReportName
oReportViewer.ShowParameterPrompts = False
oReportViewer.ShowDocumentMapButton = False
oReportViewer.DocumentMapWidth = 0
oReportViewer.ShowDocumentMapButton = False
oReportViewer.ShowFindControls = False
oReportViewer.ServerReport.Refresh()