title: 'PDFsharp cannot handle this PDF feature introduced with Acrobat 6' error while opening PDF file
body: <p>I use PDFsharp (v1.32) for merging several PDF files. I open documents using this code:</p>
  
  <pre><code>PdfDocument inputDocument = PdfReader.Open(pdfFilePath, PdfDocumentOpenMode.Import);
  </code></pre>
  
  <p>And while opening one document (with PDF version 1.5 (Acrobat 6.x)) I receive an exception: </p>
  
  <blockquote>
    <p>An unhandled exception of type 'PdfSharp.Pdf.IO.PdfReaderException' occurred in PdfSharp.dll
    Additional information: Cannot handle iref streams. The current implementation of PDFsharp cannot handle this PDF feature introduced with Acrobat 6.</p>
  </blockquote>
  
  <p>What can I do with it? I need to merge all files, I cannot just skip it. I tried to find solution, but found not answered or just very old feedback from PDFsharp Team that they are going to "fix it".</p>