title: Cannot add HtmlAgilityPack as a reference
body: <p>This shouldn't be difficult, but I can't add HtmlAgilityPack.dll as a reference in an empty C# project. Here is what I did:</p>
  
  <ol>
  <li>Downloaded HtmlAgilityPack.1.4.5.zip.</li>
  <li>Unzipped it.</li>
  <li>In the Solution Explorer, I right-clicked on References and selected 'Add Reference...'.</li>
  <li>I use Visual Studio 2008 and selected Net20/HtmlAgilityPack.dll.</li>
  </ol>
  
  <p>There is now a yellow triangle on the HtmlAgilityPack.dll and I can't edit the path in its properties. If I remove it and add it again, the same thing happens. What am I doing wrong?</p>