Timeout when sending email via SmtpClient - c#

I'm trying to send a very simple email via the SmtpClient class. I've been looking at this for hours and I've been following examples from StackOverflow and MSDN, but for some reason I get nothing but timeouts.
I've changed the hostnames and passwords, but I've added the code below.
static void Main(string[] args)
{
Int32 port = 465;
String host = "host.co.uk";
MailAddress from = new MailAddress("test#email.co.uk");
MailAddress to = new MailAddress("paul#email.co.uk");
MailMessage msg = new MailMessage(from, to);
msg.Body = "Test Body";
msg.Subject = "Test Subject";
SmtpClient client = new SmtpClient();
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.Host = host;
client.Port = port;
client.Credentials = new System.Net.NetworkCredential("test#email.co.uk", "password");
client.UseDefaultCredentials = false;
client.Send(msg);
}
As you can see, this is a console application that tries to send the email and then exits. I took it out of the main project so I could eliminate any other possible causes (apart from the actual email code).
It throws a System.Net.Mail.SmtpException with the value
The operation has timed out.
What I think is causing the problem is the credentials, because if you look at the values in 'client' it shows the Credentials property as null, despite being set in the code.
I have to admit to being stumped. Thank you in advance for any help you can offer.

Late to the party, but it may help someone...
I had this time out issue occur with a particular SMTP server, using code that had worked for years with numerous other providers (including gmail).
It turns out that Microsoft themselves don't recommend using the SmtpClient class as it doesn't support many modern protocols. They recommend MailKit (NuGet: Install-Package MailKit)as an alternative. MailKit is very similar, code-wise, so easy to switch to. It immediately solved my problem.

Related

Why can't I send e-mail from a C# app when I can send e-mail from a mail client just fine?

I have a task to troubleshoot why a C# app is failing to send automated e-mail messages. I carefully checked the source code, and could find absolutely nothing wrong.
Therefore, I tried to send e-mail from Thunderbird, the e-mail client I normally use. I specified the same SMTP relay, the same UID and password, and everything worked fine.
Trying to isolate the problem, I tried writing a very short C# console app to see what might be going wrong. I wrote the following:
using System.Net;
using System.Net.Mail;
namespace ConsoleApp3
{
class Program
{
static void Main(string[] args)
{
var client = new SmtpClient("my.server.with.ssl", 465);
client.EnableSsl = true;
client.Credentials = new NetworkCredential("uid", "pwd");
var message = new MailMessage("me#example.com", "myemail#mydomain", "Test Message Subject", "Test Message Body");
client.Send(message);
}
}
}
I entered the same credentials that I used in Thunderbird. When I run the above, I get the following error:
Unhandled Exception: System.Net.Mail.SmtpException: Failure sending mail. ---> System.IO.IOException: Unable to read data from the transport connection: net_io_connectionclosed.
How can it be that e-mail is sent just fine from Thunderbird, but the simple programming above fails to work when I try to send an e-mail from a basic C# app?
Edit I tried changing the port number to 587 as suggested in the Question that #stuartd linked to, and in that case, I get an error that says The operation timed out.
Edit I've tried using other e-mail servers and adjusting the settings, but nothing works so far. I've tried connecting to the same SMTP server that I use for my personal e-mail and it shows an error that the connection times out.
Edit I can't say why, but everything seems to be working now in spite of the fact that I didn't change any code. It seems as if something odd happened with my connection.
try using the default constructor and specify the host only.
Also some servers require that the client be authenticated before the server sends e-mail on its behalf. Try changing the value of UseDefaultCredentials
var mail = new MailMessage();
mail.From = new MailAddress("xxx#gmx.net");
mail.To.Add("yyy#gmail.com");
mail.IsBodyHtml = true;
mail.Subject = "subject";
mail.Body = "content";
var client = new SmtpClient();
client.UseDefaultCredentials = false;
client.Host = "mail.gmx.net";
client.EnableSsl = true;
client.Credentials = new NetworkCredential("user", "pass");
client.Send(mail);
if that doesn't help than tell us the server name if its the public one
Try using:
SmtpClient smtpClient = new SmtpClient("mail.mymailhost.com");
smtpClient.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;

Unable to send Email through GoDaddy SMTP

I am working on an ASP .Net MVC website and I've to send email through Godaddy smtp, Previously my site was developed in classic ASP and it was hosted on godaddy's web hosting (then it was working fine) but now I am hosting this site on IIS,
I am using following code to send email but it is not working
MailMessage msg = new MailMessage();
msg.From = new MailAddress(model.From);
msg.To.Add(model.To);
msg.Body = model.Body;
msg.Subject = model.Subject;
SmtpClient smtp = new SmtpClient("relay-hosting.secureserver.net",25);
smtp.Credentials = new NetworkCredentials("support#{myCompanyName}.com",{password});
smtp.EnableSsl = False;
smtp.Send(msg);
I have also used dedrelay.secureserver.net instead of relay-hosting.secureserver.net host (as mentioned at https://pk.godaddy.com/help/what-is-my-servers-email-relay-server-16601) but both are not working
GoDaddy does not allow relaying through their server unless you are on one of their hosting plans that includes SMTP.
You can set your credentials in webconfig like (for godaddy)
<system.net>
<mailSettings>
<smtp from="your email address">
<network host="relay-hosting.secureserver.net" port="25" />
</smtp>
</mailSettings>
</system.net>
and in c# you can use like
MailMessage message = new MailMessage();
message.From = new MailAddress("your email address");
message.To.Add(new MailAddress("your recipient"));
message.Subject = "your subject";
message.Body = "content of your email";
SmtpClient client = new SmtpClient();
client.Send(message);
It will work
Most SMTP servers are quite restrictive nowadays when it comes to outbound email. I recommend testing the parameters with an email client (or telnet, if you're into that kinda thing) before assuming that there is something wrong with the code. That might also give you an error message that helps debugging.
Some things that come to mind:
The server may check the FROM address against it's database, specifically the user account you use to authenticate. While you can put whatever you want in the header of the email, this field must be your the real address of the authenticated account and only that (no descriptive name).
The server may require the use of TLS encryption, regardless of the port.
Port 25 is quite common, but according to the official RFC mail submission should use port 587. Maybe try that.
It is possible that GoDaddy only allows connections from their own (hosting) servers to these SMTP relays.
Unless the connection fails completely (which would point to no. 4) the server should send some kind of error message at some point. As I wrote above, I would recommend testing/logging the communication, that should provide some insight.
Perhaps you should call up to your ISP, here in th Netherlands they mostly block port 25 because of malware and worms that used to send out email. It can be as simple as this. Have you tried telnetting from your local machine to the email server (telnet mailserver.io 25)? If this ends up in a time out you have your answer and the port is either filtered out at your ISP or from their end.
You can try this code
smtp.Host = "relay-hosting.secureserver.net"; smtp.EnableSsl = false; smtp.UseDefaultCredentials = false; smtp.Port = 25;
string From = "[MyGodaddyEMailAddress]"; //eg.info#mango.com
string FromPassword = "[MyGodaddyMailPassword]";
try
{
MailMessage msg = new MailMessage();
msg.From = new MailAddress(From);
msg.To.Add("[RecipientEmailAddress]");
msg.Subject = "[MailSubject]";
msg.Body = "[MailBody]";
msg.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient("mail.[domain].com", 587); //eg. mail.mango.com
smtp.Credentials = new System.Net.NetworkCredential(From, FromPassword);
smtp.EnableSsl = false;
// Sending the email
smtp.Send(msg);
// destroy the message after sent
msg.Dispose();
Console.WriteLine("Message Sent Successfully");
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
Console.ReadKey();

avast VS my Programm

I have problem with my program. I make a simple mail-messenger, and in this code :
var mail = new MailMessage();
var smtpServer = new SmtpClient("smtp.mail.ru");
smtpServer.Port = 25;
smtpServer.Credentials = new
NetworkCredential("#mail.ru", "pass");
smtpServer.EnableSsl = true;
mail.Body = text;
mail.From = new MailAddress("#mail.ru");
mail.To.Add("#mail.ru");
smtpServer.Send(mail); // in this moment
Avast find the idp generic in moment of mail send. The other antiviruses (eset32, Kaspersky,cureit) do not see problems and danger in code. I also was try to send mail with mailkit.dll. how can I fix it?
Your best bet is probably using the standard SMTP client-to-server email submission port: 587.
smtpServer.Port = 587;
If you, for whatever reason, can't use the standard email submission port, use the Avast GUI to make exceptions. Doing it through the antivirus directly should allow your program to run on your machine, and that's all you want, right? ;)
You can try:
Excluding your build directory from live scans
Authorizing your process to use port 25
Avast help pages for further reading

SMTP mail only sends internally

I've got a c# function that sends emails from the win app to me via SMTP from a gmail account.
It works, but only if the FROM parameter is internal.
When I add an external address, it runs without errors, but the email never arrives in my mailbox.
I've noticed several posts on this site with similar issues, but the difference with most seems that everyone else gets some kind of error message.
MailMessage mail = new MailMessage();
using (SmtpClient SmtpServer = new SmtpClient(smtp.gmail.com))
{
mail.From = new MailAddress("you#myGoogleDomain.com"); //This works
//mail.From = new MailAddress("me#somewhere.com"); //This does not work
mail.To.Add("recipient#myGoogleDomain.com");
mail.Subject = "Mail Subject";
mail.Body = mailBody;
mail.ReplyTo = new MailAddress("me#myGoogleDomain.com");
mail.CC.Add(new MailAddress("me#myGoogleDomain.com"));
mail.IsBodyHtml = true;
SmtpServer.Port = 587; //I've also tried 465
//SmtpServer.UseDefaultCredentials = false; //This does not make a difference.
SmtpServer.Credentials = new System.Net.NetworkCredential("myaccount#myGoogleDomain.com", "Pass123");
SmtpServer.EnableSsl = true; //I've also tried false
//Add attachments
...
//Send the mail
SmtpServer.Send(mail);
}
MORE INFORMATION: I notice that the emails sits in the myaccount#myGoogleDomain.com 'Sent' box. Just no mails coming through to recipient#myGoogleDomain.com.
You are sending email using Google smtp server on behalf of your account in Google. You can't use Google smtp with non-google account to From. Even if you are sending regular email in Gmail or other email you can't modify From. Same behavior in this code you posted.
The problem was not really with the From param, but with the ReplyTo. Since both params are set from the same variable (and not strings), it did not work when it was set to outside my domain.
Removing the ReplyTo settings solved the problem.

Issue in receiving emails [duplicate]

This question already has answers here:
The SMTP server requires a secure connection or the client was not authenticated
(3 answers)
Closed 8 years ago.
I am doing my project in mvc4 using c#. I have a contact page i my website. My need is that i have to receive messages to my email id from other id's, when clicking the Send button.I use the following code
public void ReceiveMail(string name,string email,string message)
{
MailMessage msg = new MailMessage();
HttpContext ctx = HttpContext.Current;
msg.To.Add(new MailAddress("MyEmailId"));
msg.From = new MailAddress(email);
msg.Subject =name + "send a message";
msg.Priority = MailPriority.High;
msg.Body = message;
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");// i am confused what to write here
SmtpServer.Send(msg);
}
It shows the error
The SMTP server requires a secure connection or the client was not authenticated.
The server response was: 5.7.0 Must issue a STARTTLS command first.
at4sm42219747pbc.30 - gsmtp
I don't know from which server i got the mail. Then how can i solve this issue . Please help me
Sending emails with Gmail requires some additional settings. At first, port number should be 587 (instead of default 25). At second, Gmail requires secure connection. And of course you should provide valid credentials.
All in all, initialization of SmtpClient should look like this:
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com", 587);
SmtpServer.EnableSsl = true;
SmtpServer.Credentials = new NetworkCredential("username#gmail.com", "password");
as the error says, a STARTTLS command should be used first. Thas means gmail only accepts mail via secure connection. In this answer enableSsl was set to true. As the documentation from microsoft says, the SmtpClient class has such an property too. Furthermore you should leave your credentials in the smptClient. I think gmail only accepts mail from authenticate users. I think the whole problem is solved here.
You need to use NetworkCredential to login into Gmail SMTP server. Error is very apparent.
SmtpClient smtp = new SmtpClient("smtp.gmail.com", 587);
smtp.EnableSsl = true;
smtp.UseDefaultCredentials = false;
smtp.Credentials = new NetworkCredential("your-email", "your-password");
Have you tried:
smtpServer.Host = "smtp.gmail.com";
smtpServer.Port = 587;
smtpServer.Credentials =
new NetworkCredential("SenderGmailUserName", "SenderPassword");

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