How Can I Fix Webexception ?

public static void UpLoadImage(string source)
        {
            
            try
            {
                string filename = System.IO.Path.GetFileName(source);
               // string ftpfullpath = ftpurl;
                FtpWebRequest ftp = (FtpWebRequest)WebRequest.Create("ftp://192.168.0.41");
               // ftp.Credentials = new NetworkCredential(ftpusername, ftppassword);

                MessageBox.Show(ftp.GetResponse().ToString());

                ftp.KeepAlive = true;
                ftp.UseBinary = true;
                ftp.Method = WebRequestMethods.Ftp.UploadFile;

                FileStream fs = File.OpenRead(source);
                byte[] buffer = new byte[fs.Length];
                fs.Read(buffer, 0, buffer.Length);
                fs.Close();

                Stream ftpstream = ftp.GetRequestStream();
                ftpstream.Write(buffer, 0, buffer.Length);
                ftpstream.Close();
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }