ExecuteNonQuery: Connection property has not been initialize

Question

String strConnString = ConfigurationManager.ConnectionStrings["EMPLOYEEConnectionString2"].ConnectionString;

        //SqlConnection con = new SqlConnection();

        protected void btnSave_Click(object sender, EventArgs e)

        {

          SqlConnection con = new SqlConnection(strConnString);

            con.Open();

         //   con.ConnectionString = new SqlConnection(strConnString);

            SqlCommand cmd = new SqlCommand();

            cmd.CommandType = CommandType.StoredProcedure;

            cmd.CommandText = "JOINMAX";

            cmd.Parameters.Add("@NAME", SqlDbType.VarChar).Value = txtName.Text.Trim();

            cmd.Parameters.Add("@EMAIL", SqlDbType.VarChar).Value = txtEMAIL.Text.Trim();

            cmd.Parameters.Add("@PHONENO", SqlDbType.VarChar).Value = txtPHONE.Text.Trim();

            cmd.Parameters.Add("@ERROR", SqlDbType.Char, 500);

            cmd.Parameters["@ERROR"].Direction = ParameterDirection.Output;

            cmd.ExecuteNonQuery();

            //  Label1.Text = "Record inserted successfully";

string message = (string)cmd.Parameters["@ERROR"].Value;

            con.Close();

        }

    }

}