SmtpClient: A connection attempt failed because the connected party did not properly respond after a period of time

问题

While working with Email sending in C#.NET in visual studio 2008 i got the below error

A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 74.125.53.108:25

But the same code was working fine in some other PC but when i am testing today it gives me error in Send() method... Also my network connection is good where i am testing the email code..

Below is my email code

MailMessage mail = new MailMessage();
mail.To.Add(to);
mail.From = new MailAddress(from);
mail.Subject = subject;
mail.Body = body;
mail.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient();
smtp.Host = "smtp.gmail.com";
smtp.Credentials = new System.Net.NetworkCredential("MyUserName@gmail.com",
                                                            "MyPassword");
smtp.EnableSsl = true;
smtp.Send(mail);

What could be the reasons for such error..???

回答1:

The following code works for me. Your code was giving me errors, I believe it was due to not setting the port to 587.

http://forums.asp.net/t/1250771.aspx/4/10

MailMessage mail = new MailMessage();
mail.To.Add(to);
mail.From = new MailAddress(from);
mail.Subject = subject;
mail.Body = body;
mail.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient("smtp.gmail.com",587);
smtp.EnableSsl = true;
smtp.UseDefaultCredentials = false;
smtp.Credentials = new System.Net.NetworkCredential(address, password);
smtp.Send(mail);

回答2:

This happened to me due to my company security wifi. Once I changed to open wifi, the problem was solved automatically.

来源：https://stackoverflow.com/questions/7102687/smtpclient-a-connection-attempt-failed-because-the-connected-party-did-not-prop

标签

gmail

smtpclient