Dim hiddenRows As List(Of GridViewRowInfo) = New List(Of GridViewRowInfo)()
 Private Sub radGridView1_ViewCellFormatting(sender As Object, e As UI.CellFormattingEventArgs) _
     Handles radGridView1.ViewCellFormatting

     '  hide summary row except when exporting
     If TypeOf e.CellElement Is GridSummaryCellElement Then
         e.Row.IsVisible = Me.Exporting
         If Not Me.hiddenRows.Contains(e.Row) Then
             Me.hiddenRows.Add(e.Row)
         End If
     End If

 End Sub

 Private Sub btnExport_Click(sender As Object, e As EventArgs) Handles RadAButton1.Click

     Me.Exporting = True
     For Each row As GridViewRowInfo In Me.hiddenRows
         row.IsVisible = Me.Exporting
     Next
     Me.radGridView1.TableElement.Update(GridUINotifyAction.StateChanged)


     Dim file As String = "C:\TEMP\ExportText.xlsx"

     '  delete file if it exists
     If System.IO.File.Exists(file) = True Then
         System.IO.File.Delete(file)
     End If

     Dim spreadExporter As GridViewSpreadExport = New GridViewSpreadExport(Me.radGridView1)
     Dim exportRenderer As New SpreadExportRenderer()

     spreadExporter.ExportVisualSettings = True
     spreadExporter.ExportGroupedColumns = True
     spreadExporter.HiddenRowOption = UI.Export.HiddenOption.ExportAlways
     spreadExporter.SummariesExportOption = UI.Export.SummariesOption.ExportAll
     spreadExporter.RunExport(file, exportRenderer)

     Process.Start(file)
     Me.Exporting = False
     For Each row As GridViewRowInfo In Me.hiddenRows
         row.IsVisible = Me.Exporting
     Next
     Me.radGridView1.TableElement.Update(GridUINotifyAction.StateChanged)
 End Sub