title: Conversion from HTML to pdf generates an exception
body: <p>I have a small C# desktop application that creates a pdf file given some HTML, retrieved from an *.eml file. 
  Here is a sample:</p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
   &lt;meta http-equiv="Content-Type" content="text/html; charset=utf-8" /&gt;
  &lt;/head&gt;
  &lt;body&gt;
   &lt;div style="font: normal 13px Arial; color:#000000;"&gt;
    &lt;p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt"&gt;&lt;font size="3"&gt;&lt;font face="Calibri"&gt;Some text&lt;o:p&gt;&lt;/o:p&gt;&lt;/font&gt;&lt;/font&gt;&lt;br /&gt;
    &lt;/p&gt;
    &lt;p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt"&gt;&lt;o:p&gt;&lt;font size="3" face="Calibri"&gt;&amp;nbsp;&lt;/font&gt;&lt;/o:p&gt;&lt;br /&gt;
     &lt;span style="FONT-SIZE: 11pt; FONT-FAMILY: &amp;quot;Calibri&amp;quot;,&amp;quot;sans-serif&amp;quot;; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-bidi-font-family: &amp;quot;Times New Roman&amp;quot;; mso-fareast-language: EN-US; mso-ascii-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-theme-font: minor-bidi; mso-ansi-language: IT; mso-bidi-language: AR-SA"&gt;Some other text&lt;/span&gt;
    &lt;/p&gt;
   &lt;/div&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>Everything works just fine on my machine (Win10 x64), however when I run the same code on the client's machine (Win Server 2008 R2 x64), I get the "document has no pages" message from an iTextsharp exception.</p>
  
  <p>This only happens sometimes, for specific HTML strings like the one I just posted; I can't run a debugging session on the client's machine, however I verified that the program receives well formed HTML (as it is parsed with the HTML Agility Pack).</p>
  
  <p>Can this be a font-related issue? I have absolutely no clue, these seem to be present on the client's machine.</p>
  
  <p>Here is a snippet of the code I use to create the pdf document (it uses a custom image tag processor, though it should not be the issue since there isn't any in the given snippet):</p>
  
  <pre><code>using (var document = new Document())
  {
      var writer = PdfWriter.GetInstance(document, new FileStream(destinationPath, FileMode.Create));
      writer.CompressionLevel = PdfStream.BEST_COMPRESSION;
      document.Open();
  
      var tagProcessors = (DefaultTagProcessorFactory)Tags.GetHtmlTagProcessorFactory();
      tagProcessors.RemoveProcessor(HTML.Tag.IMG);
      tagProcessors.AddProcessor(HTML.Tag.IMG, new CustomImageTagProcessor());
      CssFilesImpl cssFiles = new CssFilesImpl();
      cssFiles.Add(XMLWorkerHelper.GetInstance().GetDefaultCSS());
      var cssResolver = new StyleAttrCSSResolver(cssFiles);
      cssResolver.AddCss(@"code { padding: 2px 4px; }", "utf-8", true);
      var charset = Encoding.UTF8;
      var hpc = new HtmlPipelineContext(new CssAppliersImpl(new XMLWorkerFontProvider()));
      hpc.SetAcceptUnknown(true).AutoBookmark(true).SetTagFactory(tagProcessors);
      var htmlPipeline = new HtmlPipeline(hpc, new PdfWriterPipeline(document, writer));                            
      var pipeline = new CssResolverPipeline(cssResolver, htmlPipeline);
      var worker = new XMLWorker(pipeline, true);
      var xmlParser = new XMLParser(true, worker, charset);
      xmlParser.Parse(new StringReader(fixedMarkup));
  }
  </code></pre>