I am trying to send email using Exchange 2007 from a console app using the following code and I get this error message in the exception that gets thrown on the Send call.
The SMTP server requires a secure
connection or the client was not
authenticated. The server response
was: 5.7.1 Client was not
authenticated
MailMessage message = new MailMessage();
message.From = new MailAddress("from#example.com");
message.To.Add("to#domain.com");
message.Subject = "test";
SmtpClient smtp = new SmtpClient(ConfigurationUtil.SMTPServer);
smtp.Credentials = new System.Net.NetworkCredential("from#example.com", "password");
smtp.Send(message);
This worked on Exchange 2003.
This ended up being an Exchange 2007 issue and had nothing to do with code.
From the error message it seems like you need to connect to Exchange via SSL.
SmtpClient smtp = new SmtpClient(ConfigurationUtil.SMTPServer, 465);
Substitute that port number for the port that your Exchange server's secure connection is listening on.
Related
I desperately need help solving this issue. How can I get my deployed app to send emails to any address via SMTP?
I am developing a web-based sales-tracking application in Visual Studio 2015 (ASP.NET MVC). The site will be hosted on an Arvixe BusinessClass for Windows shared server. The domain of the server is mydomain.com, however this domain is actually hosted by one.com, which also provides mydomain.com email.
One of the functions of the site is to inform the line manager when a user reports a sale. The line manager is to be informed via email. The email account I am trying to send from is provided by one.com.
Using System.Net.Mail.MailMessage and sending via SmtpClient, trhe following code works in my development environment (Windows 10 pro) but not deployed (deployed on Arvixe BusinessClass for Windows shared server environment):
MailMessage message = new MailMessage();
message.To.Add("recipient#mydomain.com");
message.From = new MailAddress("sender#mydomain.com", "sender#mydomain.com");
message.IsBodyHtml = true;
message.Subject = "Subject";
message.Body = "Body<br />";
SmtpClient client = new SmtpClient();
client.DeliveryFormat = SmtpDeliveryFormat.SevenBit;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Host = "send.one.com";
client.Port = 587;
client.UseSSL = true;
client.Credentials = new NetworkCredential("sender#mydomain.com", "***");
client.Send(message);
On my Arvixe server I get the error:
"Unable to read data from the transport connection: net_io_connectionclosed".
Using this code I have also tried ports 465 and 25, with SSL set to true and false, and also host "mailout.one.com", without success.
I gave up and tried using MailKit with the following code:
MimeMessage message = new MimeMessage();
message.To.Add(new MailboxAddress("recipient#mydomain.com"));
message.From.Add(new MailboxAddress("sender#mydomain.com", "sender#mydomain.com"));
var bodyBuilder = new BodyBuilder();
bodyBuilder.HtmlBody = "htmlbody<br />";
bodyBuilder.TextBody = "textbody";
message.Body = bodyBuilder.ToMessageBody();
message.Subject = "Subject";
using (var client = new SmtpClient())
{
client.ServerCertificateValidationCallback = (s, c, h, e) => true;
client.Connect("send.one.com", 587, MailKit.Security.SecureSocketOptions.StartTls);
client.Authenticate("sender#mydomain.com", "***");
client.Send(message);
client.Disconnect(true);
}
Again it works in my development environment, but not in production. Here I get the error:
"The operation is not allowed on non-connected sockets".
Of note, both solutions work in deployed environment if I change the host to 127.0.0.1 and add an example#mydomain.com email account and connected user account in Arvixe, but only for external email addresses. Addresses ending in mydomain.com obviously get rerouted back to the server itself, as the server's domain is mydomain.com, but as the email provider is one.com and not the Arvixe server, the email doesn't get through.
Other things I have tried without success:
-Setting the SPF record for mydomain.com to include my server address, and my server IP address.
-Using an Office365 account on a different domain to send from (host "smtp.office365.com")
I desperately need help solving this issue. How can I get my deployed app to send emails to any address via SMTP?
Arvixe/One.com suggestions (from support tickets and live chat):
SMTP Authentication must be used.
The local mail server, or localhost must be used to send email via web script. (try xxx.win.arvixe.com, localhost, or 127.0.0.1 - port 25 or 26, or xxxsecuremail.win.arvixe.com - port 465 for secure mail)
The FROM email address, and SMTP Authentication email address, must be a local user on the local server.
If you have your own remote email server and intend to send emails via web script to email addresses that are local to your domain, then that mail domain needs to be removed from the local server (we have to do this) and you will have to use an account from another domain local to the server to send mail from. Otherwise any email going to the local domain will be delivered locally and not to your remote server.
Server: VDS
OS: Windows Server 2008 R2
Application: None
Library (DLL used by an application): Yes, C#
I am trying to send mail via C# using from what I read, gmail service. Basically just a test email to myself would be a start to know it works. If you have to ask, the information is stored in config.json file rather than directly in the code, hence the "AccountRecovery.AccountRecoveryConfig".
I cannot seem to get it to work! When using certain ports I get different errors!
PORT 465 - With Credentials
ERROR:
2016-02-05 02:52:33 - Command: ERROR: System.Net.Mail.SmtpException: Failure sending mail. ---> System.IO.IOException: Unable to read data from the transport connection: net_io_connectionclosed.
PORT 587 - With Credentials
ERROR:
2016-02-05 02:55:50 - Command: ERROR: System.Net.Mail.SmtpException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at
I have no idea what to do. Am I doing something wrong?
public static void SendEmail(string email)
{
MailMessage mail = new MailMessage(AccountRecovery.AccountRecoveryConfig.ServerEmailAddress, email);
SmtpClient client = new SmtpClient();
client.Timeout = 30000;
client.Host = AccountRecovery.AccountRecoveryConfig.HostSMTPServer;
client.Port = AccountRecovery.AccountRecoveryConfig.HostPort;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential(AccountRecovery.AccountRecoveryConfig.ServerEmailAddress, AccountRecovery.AccountRecoveryConfig.ServerEmailPassword);
client.EnableSsl = true;
//client.ServicePoint.MaxIdleTime = 1;
mail.Subject = AccountRecovery.AccountRecoveryConfig.EmailSubjectLine;
mail.Body = AccountRecovery.AccountRecoveryConfig.EmailBodyLine;
mail.IsBodyHtml = false;
client.Send(mail);
}
The correct port is 587 for google, this error:
2016-02-05 02:55:50 - Command: ERROR: System.Net.Mail.SmtpException:
The SMTP server requires a secure connection or the client was not
authenticated. The server response was: 5.5.1 Authentication Required.
Learn more at
You should give access to less secure applications. Here is the LINK where you can do it for your current logged google account.
I having problem on sending message on the server. But in my local I can send message to the emails using the free smtp server.
Maybe there's a firewall or localhost is not accepted in the email policy?
Please advise.. thanks!
Code:
//send email
MailMessage objEmail = new MailMessage(new MailAddress(ConfigurationManager.AppSettings["emailAdd"].ToString()), new MailAddress(ConfigurationManager.AppSettings["emailAdd"].ToString()));
objEmail.Subject = "Test";
objEmail.Body = _Message;
objEmail.Priority = MailPriority.High;
SmtpClient SmtpMail = new SmtpClient();
SmtpMail.Host = "localhost";
SmtpMail.Send(objEmail);
Error:
System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: 5.7.1 Unable to relay for mae#yahoo.com
at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
This blog post answers basically the same question. Assuming you are sending through the IIS SMTP server, you may need to modify the Relay Restrictions to allow relaying from your IP address.
Few checks:
Check if your proxy is not blocked if using
Check that your server IP is in white-list, if it is being maintained on mail server
On mail server check if no password is required
Smtp server address is fine
I want to send email using the SMTP client in C#. Currently I am using this code:
System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
message.To.Add("receiver");
message.Subject = "";
message.From = new System.Net.Mail.MailAddress("sender");
message.Body = "This is a test mail";
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");
smtp.Credentials = new System.Net.NetworkCredential("username", "password");
smtp.Port = 587;
smtp.EnableSsl = true;
smtp.Send(message);
But I want to send mail with out using username and password by just providing the sender address. Is this possible in C#?
Is this possible with any SMTP server(Not google). I mean login to server anonymously and just provide your mail address.
No. Gmail does not allow anonymous senders. Thankfully.
If it was possible anyone could pretend to send emails from everyone else, rendering gmail as one big spam engine.
It depends on your server. In your code you are using Gmail and Gmail requires this.
You can set up your own SMTP server.
The SMTP server in IIS allows this per default if your application is on the same server as IIS.
In the end you'll have to send credentials if the server demands them.
You could send the credentials of the current security context if that's what you're looking for. See: http://msdn.microsoft.com/en-us/library/system.net.credentialcache.defaultnetworkcredentials.aspx.
I set up my hMailServer on my windows 2008 machine, and I'm trying to send emails.
When I do it with C#
MailMessage message = new MailMessage();
message.From = new MailAddress(from, "John");
message.To.Add(new MailAddress(to));
message.Subject = subject;
message.Body = body;
SmtpClient client = new SmtpClient("mail.example.com");
client.Credentials = new System.Net.NetworkCredential("john#example.com", "password");
client.Send(message);
But when I try to send emails with a windows live email client, it gives me an error
The connection to the server has failed
All the settings are exactly the same. I tried several email clients, but it doesn't work. It never happened to me before. I just moved from one machine to another, and got this problem.
I can receive mail in the client though...
Try to telnet to port 25, can it connect?
Open up command prompt:
telnet mail.example.com 25
If it cannot connect (which is what I expect) then you have a problem that is not code related but firewall related. (Or perhaps you're trying to connect to the wrong port if they're running SMTP on a non standard port)