Digital signature on documents

private void CreateNewPage()
  {
      object missing = System.Reflection.Missing.Value;
      object fileName = @"F:\Doc\test.docx";
      object readOnly = false;
      object isVisible = true;

      //Start Word and open a document.
      Microsoft.Office.Interop.Word._Application oWord;
      Microsoft.Office.Interop.Word._Document oDoc;
      oWord = new Microsoft.Office.Interop.Word.Application();
      oWord.Visible = true;

      oDoc = oWord.Documents.Open(ref fileName, ref missing, ref readOnly,
          ref missing, ref missing, ref missing, ref missing, ref missing,
          ref missing, ref missing, ref missing, ref isVisible, ref missing,
          ref missing, ref missing, ref missing);

      //  var numberOfPages = oDoc.ComputeStatistics(Word.WdStatistic.wdStatisticPages, false);

      object oEndOfDoc = "\\endofdoc";
      object paramNextPage = Microsoft.Office.Interop.Word.WdBreakType.wdSectionBreakNextPage;

      oDoc.Bookmarks.get_Item(ref oEndOfDoc).Range.InsertBreak(ref paramNextPage);
      //Insert a page break
      object breakPage = Microsoft.Office.Interop.Word.WdBreakType.wdPageBreak;


      object saveOption = Microsoft.Office.Interop.Word.WdSaveOptions.wdDoNotSaveChanges;
      object originalFormat = Microsoft.Office.Interop.Word.WdOriginalFormat.wdOriginalDocumentFormat;
      object routeDocument = false;

      object what = Microsoft.Office.Interop.Word.WdGoToItem.wdGoToPage;
      object which = Microsoft.Office.Interop.Word.WdGoToDirection.wdGoToLast;
      object count = 3;

      oWord.Selection.GoTo(ref what, ref which, ref count, ref missing);

      object sigID = "{00000000-0000-0000-0000-000000000000}";


      try
      {
          oWord.Activate();

          SignatureSet signatureSet = oWord.ActiveDocument.Signatures;
          // signatureSet.ShowSignaturesPane = false;
          Signature objSignature = signatureSet.AddSignatureLine(sigID);
          objSignature.Setup.SuggestedSigner = "docSigner";
          objSignature.Setup.SuggestedSignerEmail = "abc@xyz.com";
          objSignature.Setup.ShowSignDate = true;
          //  dynamic shape = objSignature.SignatureLineShape;
      }
      catch (Exception ex) { MessageBox.Show(ex.Message); }

      oWord.Documents.Save();
      oWord.Quit();

      try
      {
          Marshal.ReleaseComObject(oWord);
      }
      catch (Exception e) { MessageBox.Show(e.Message); }
  }