Send file to iPhone/Android from ASP website

Guys I have website (ASP WebForms) In website user can upload and download files. For computer it working good. But Download not working for mobile(upload working) I have Electric Plum for debug with iPhone - and Emulator was closed in this lines :

//Reading the file stream and writing it to page.
                FileStream inStream = File.Open(FilePath, FileMode.Open, FileAccess.Read, FileShare.Read);
                outStream.Flush();
                long fileSize = inStream.Length;
                long bytesSent = 0;
                byte[] buf = new byte[64 * 1024];
                int bytesRead = inStream.Read(buf, 0, buf.Length);
                while (bytesRead > 0 && context.Response.IsClientConnected)
                {
                    try
                    {
                        //For Mobile Version need check if we can send file via Stream
                        outStream.Write(buf, 0, bytesRead);
                        outStream.Flush();
                        bytesSent += bytesRead;
                        bytesRead = inStream.Read(buf, 0, buf.Length);
                    }
                    catch
                    {
                        bytesRead = 1;
                    }

in this line:

outStream.Write(buf, 0, bytesRead);
                            outStream.Flush();
                            bytesSent += bytesRead;
                            bytesRead = inStream.Read(buf, 0, buf.Length);

outStream it System.IO.Stream So i think problem with Stream. So guys if somebody have idea how i can resolve it - please write here.

Thank you!!!