Hi, i'm trying to send an email through smtp client in asp.net. It's ending with an error saying "Failure sending mail" and having inner exception as "Unable to read data from the transport connection: net_io_connectionclosed". I've tried surfing google to get this resolved and found few smtp.ServicePoint parameters to be setup but all that didn't work.
What i've come to know from my client is that the Mail Service is acquired from "networkdogsinc.com" and the mail address is an Exchange email. So far i've worked simple mail servers in asp.net and has developed working solutions but with Exchange Server it's my first experience. Also i didn't know how to access the "mail.combslawgroup.com" directly other than code or any mailing tool like outlook.
Please review the code attached for reference. Note that the From and To email address is same in this case (because this is for a Contact us page). Also the SMTPUid and SMTPPwd parameters in real code.
Please any one there to help me to get this resolved as it's a problem on one of my live sites.
MailMessage email = new MailMessage();
email.From = new MailAddress("firstname.lastname@example.org");
email.Subject = "Contact Us Email Subject";
email.Body = "email body";
SmtpClient smtp = new SmtpClient("mail.combslawgroup.com");
smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
smtp.ServicePoint.MaxIdleTime = 1000;
smtp.ServicePoint.ConnectionLimit = 1;
email.IsBodyHtml = true;
smtp.UseDefaultCredentials = true;
smtp.Credentials = new System.Net.NetworkCredential("SMTPUid", "SMTPPwd");
return "Your request has been submitted successfully.";
catch (Exception ex)
return "An error occured while sending email to admin. Error :: " + ex.Message;