title: Can't open file from IE when using content-disposition attachment and very long file name
body: <p>I'm using very simple code to download file from ASP .NET web-application. The problem is in Internet Explorer when file name length is 134 symbols and more. The standard dialog box is shown ("Do you want to open or save 123456789012345678901234567890123456....pdf from localhost?"). But when clicking "Open" button nothing happens. There is no problem, when file name length is shorter, i.e. 133.</p>
  
  <p>My code:</p>
  
  <pre><code>string fileName = "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890.pdf";
  byte[] fileData = File.ReadAllBytes(Server.MapPath("~/document.pdf"));           
  
  Response.Clear();
  Response.ContentType = "application/pdf";
  Response.AppendHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
  Response.OutputStream.Write(fileData, 0, fileData.Length);
  Response.Flush();
  Response.End();
  </code></pre>