Error - 'The SMTP server requires a secure connection or the client was not authenticated RSS

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  jagjit saini

  Member

  24 Points

  90 Posts

  Error - 'The SMTP server requires a secure connection or the client was not authenticated

  Dec 30, 2020 02:32 AM|jagjit saini|LINK

  protected void sendEmail(string address, string subject, string from, string body)
          {
              System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
              message.To.Add(address);
              message.Subject = subject;
              message.From = new System.Net.Mail.MailAddress(from);
              message.Body = body;
              System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");
              smtp.Credentials = new System.Net.NetworkCredential("test@gmail.com", "xxxx");
  
              smtp.Port = 587;
              smtp.EnableSsl = true;
              smtp.Send(message);
  
          }

  
  Hi

  <div>protected void sendEmail(string address, string subject, string from, string body)</div> <div>        {</div> <div>            System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();</div> <div>            message.To.Add(address);</div> <div>            message.Subject = subject;</div> <div>            message.From = new System.Net.Mail.MailAddress(from);</div> <div>            message.Body = body;</div> <div>            System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");</div> <div>            smtp.Credentials = new System.Net.NetworkCredential("abc@gmail.com", "XXXXX");</div> <div>            smtp.Port = 587;</div> <div>            smtp.EnableSsl = true;</div> <div>            smtp.Send(message);</div> <div> </div> <div>        }</div>

  Thanks

• • Reply
  XuDong Peng

  Participant

  1780 Points

  553 Posts

  Re: Error - 'The SMTP server requires a secure connection or the client was not authenticated

  Dec 31, 2020 02:41 AM|XuDong Peng|LINK

  Hi jagjit saini,

  I'm not sure if you have modified the setting in Less secure app access setting to "turn on", so that you can use gmail to send mail in third-party applications.

  According to the code you provided, you also need to set UseDefaultCredentials property to "false", something like this:

  protected void sendEmail(string address, string subject, string from, string body)
          {
              System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
              message.To.Add(address);
              message.Subject = subject;
              message.From = new System.Net.Mail.MailAddress(from);
              message.Body = body;
              System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");
              smtp.Credentials = new System.Net.NetworkCredential("test@gmail.com", "xxxx");
  
              smtp.Port = 587;
              smtp.EnableSsl = true;
              smtp.UseDefaultCredentials = false;
              smtp.Send(message);
  
          }

  Hope this can help you.

  Best regards,

  Xudong Peng

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