title: C# http download with large files (300 Mb) stops after a few minutes (after 80 Mb)
body: <p>I use the following code to send a .zip file to a customer, it works great for files around 60-80 Mb but when I try with larger files (300 Mb) customers report that the browser (both IE and FFX) just stops download progress after a few minutes (around (80Mb)) and nothing more happens.</p>
  
  <p>I wonder if there could be a setup issue with IIS that stops the request handling thread to execute after a few minutes or if there is anything wrong with my code.</p>
  
  <p>I could obviously find other ways to deliver .zip files but this issue is bothering me a bit and I want to get it working.</p>
  
  <p>The code:</p>
  
  <pre><code>        Response.ContentType = "application/zip";
  
          Response.AddHeader("Content-Disposition", "attachment; filename=" + "hands.zip");
          var fi = new FileInfo(dld.Path);
          Response.AddHeader("Content-Length", fi.Length.ToString());
          const int buffercnt = 50000;
          var buffer = new byte[buffercnt];            
          using (var br = new BinaryReader( new StreamReader(dld.Path).BaseStream))
          {
              int read = br.Read(buffer, 0, buffercnt);
              while(read != 0)
              {
                  Response.OutputStream.Write(buffer, 0, read);
                  read = br.Read(buffer, 0, buffercnt);
                  Response.Flush();
              }           
          }
      Response.Close();
      Response.End();
  </code></pre>