Send email without password in ASP.NET

string to = "adhikar.patil@gmail.com";
            string from = "adhikar.patil@gmail.com";
            MailMessage message = new MailMessage(from, to);

            System.Text.StringBuilder sb = new System.Text.StringBuilder();

            sb.Append("<table>");
            sb.AppendFormat("<tr><td>Name:</td><td>{0}</td></tr>", txtName.Text.Trim());
            sb.AppendFormat("<tr><td>Email:</td><td>{0}</td></tr>", txtEmail.Text.Trim());
            sb.AppendFormat("<tr><td>Phone No</td><td>{0}</td></tr>", txtPhoneNo.Text.Trim());
            sb.AppendFormat("<tr><td>Organisation:</td><td>{0}</td></tr>", txtOrganisation.Text.Trim());          
            sb.Append("<table>");
           
            message.Subject = "BDS Contacted by " + txtName.Text;
            message.Body = sb.ToString();
            //message.BodyEncoding = Encoding.UTF8;
            message.IsBodyHtml = true;
            SmtpClient client = new SmtpClient("smtp.gmail.com", 587);
            System.Net.NetworkCredential basicCredential1 = new
            System.Net.NetworkCredential("abc@gmail.com", "abc");
            client.EnableSsl = true;
            client.UseDefaultCredentials = false;
            client.Credentials = basicCredential1;
            try
            {
                client.Send(message);
            }
            catch (Exception ex)
            {
                throw ex;
            }