title: iTextSharp - Digital Signature Issue on Pdf File
body: <p>I am using iTextSharp to add digital signature to a new pdf. The digital signature is placed on the file as expected. However, when i click in the box its not actually allowing me to select my digital signature to sign with.</p>
  
  <p>I have opened one of our companies other pdf files, that allows digital signature, just to test that my signature is working. When i click in the box in this pdf, it allows me to choose digital signature; so i know my signature does work.</p>
  
  <p>Anyone know what causes this issue? The code to add the signature to the pdf, i am using for testing, is below:</p>
  
  <p>Any help would be greatly appreciated.</p>
  
  <pre><code>using (Document document = new Document())
          {
              PdfWriter writer = PdfWriter.GetInstance(document, new System.IO.FileStream(@"C:\Users\myusername\Desktop\test.pdf", System.IO.FileMode.Create));
              document.Open();
              document.Add(new Paragraph("A paragraph"));
              PdfFormField sig = PdfFormField.CreateSignature(writer);
              sig.SetWidget(new Rectangle(100, 100, 250, 150), null);
              sig.FieldName = "testSignature";
              sig.Flags = PdfAnnotation.FLAGS_PRINT;
              sig.SetPage();
              sig.MKBorderColor = BaseColor.BLACK;
              sig.MKBackgroundColor = BaseColor.WHITE;
              PdfAppearance appearance = PdfAppearance.CreateAppearance(writer, 72, 48);
              appearance.Rectangle(0.5f, 0.5f, 71.5f, 47.5f);
              appearance.Stroke();
              sig.SetAppearance(
                PdfAnnotation.APPEARANCE_NORMAL, appearance
              );
              writer.AddAnnotation(sig);
          }
  </code></pre>