************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.WinControls.RichTextEditor.UI.PasteOptionsPopup.OnRichTextBoxLayoutUpdated(Object sender, EventArgs e)
   at Telerik.WinControls.Layouts.ContextLayoutManager.fireLayoutUpdateEvent()
   at Telerik.WinControls.Layouts.ContextLayoutManager.UpdateLayout()
   at Telerik.WinForms.Documents.UI.DocumentPrintPresenter.Telerik.WinForms.RichTextEditor.IDocumentEditorPresenter.UpdateLayout()
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.<>c__DisplayClass653_0.<UpdateEditorLayout>b__0()
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.UpdateEditorLayout(Boolean focusCarret, Boolean updateCaretSize, Boolean async)
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.set_ActiveEditorPresenter(IDocumentEditorPresenter value)
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.Telerik.WinControls.UI.IPrintable.BeginPrint(RadPrintDocument sender, PrintEventArgs args)
   at Telerik.WinControls.UI.RadPrintDocument.OnBeginPrint(PrintEventArgs e)
   at System.Drawing.Printing.PrintDocument._OnBeginPrint(PrintEventArgs e)
   at System.Drawing.Printing.PrintController.Print(PrintDocument document)
   at System.Drawing.Printing.PrintDocument.Print()
   at System.Windows.Forms.PrintPreviewControl.ComputePreview()
   at System.Windows.Forms.PrintPreviewControl.CalculatePageInfo()
   at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
   at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
   at System.Windows.Forms.Control.InvokeMarshaledCallbacks()

this.radRichTextEditor1.Text = null;

radRichTextEditor1.ChangeFontStyle( FontStyle.Underline);

radRichTextEditor1.ToggleUnderline();

((MiniToolBarBase)this.radRichTextEditor1.RichTextBoxElement.PasteOptionsPopup).Hide();

private void RadRichTextEditor1_CommandExecuted(object sender, Telerik.WinForms.Documents.RichTextBoxCommands.CommandExecutedEventArgs e)
{
    if (e.Command is InsertTableCommand)
    {
        var table = radRichTextEditor1.Document.CaretPosition.GetCurrentTable();
       
        table.TableIndent = 0;  
        
        if (table != null)
        {
            foreach (var row in table.Rows)
            {
                foreach (var cell in row.Cells)
                {
                    foreach (var block in cell.Blocks)
                    {
                        var paragrpah = block as Paragraph;
                        if (paragrpah != null && paragrpah.LeftIndent < 0)
                        {
                            paragrpah.LeftIndent = 0;
                            paragrpah.HangingIndent = 0;
                        }
                    }
                }
            }
        }
        radRichTextEditor1.RichTextBoxElement.Document.UpdateLayout();
    }
}