I am given a task to create a new smtp mail server which can receive mail using C#.
While going through the articles i read we can send emails via SMTP but we have to receive or read using POP.
I was directed to links by some stackoverflow already existing questions:
Rnwood and sourceforge
Rnwood I am sorry but i did not understand how to use it.
source forge the msi asked to download if we run it, it asks to download framework 1.1.4322 which will not install in my system and throw error.
Usually there are codes for sending messages so I tried msdn example
I used localhost as the server and 587 as the port.
which gives me error (for any port 587,25)
I also found an article here which actually monitors the localhost and specified port when I try to run the msdn code.
But still I am unable to send email to test in any way.
So is there any way I can code to set up smtp in my own server and receive email and test.
Setting up and configuring a mail server is a completely different ball game than just sending or reading emails from an existing IMAP / POP3 server.
A mail server consists of a number of components such as:
A Mail Transfer Agent (MTA) that handles SMTP traffic and which is responsible for sending email from your users to an external MTA and to receive email from an external MTA.
Mail Delivery Agent which retrieves mail from the MTA and places it in the recipient's mailbox.
A domain name with appropriate DNS records and an SSL certificate.
A server that provides IMAP / POP3 functionality.
In short... stick to publicly available mail servers...
In your post you referenced the SmtpClient from the .NET framework. That library is used to connect to an existing mail server. You can use it like this.
MailMessage message = new MailMessage();
message.From = new MailAddress("your.email.address#example.com", "Your name");
MailAddress recipientsMailAddress = new MailAddress("the.recipients.email#example.com");
message.To.Add(recipientsMailAddress);
message.Subject = "The subject of your email";
message.Body = "The body / content of your email";
message.IsBodyHtml = false; // You can set this to true if the body of your email contains HTML
SmtpClient smtpClient = new SmtpClient
{
Credentials = new NetworkCredential("Your username/email", "Your password"),
EnableSsl = true, // Will be required by most mail servers
Host = "The host name of the mail server", //
Port = 465 // The port number of the mail server
};
smtpClient.Send(message);
If you have a Gmail account, you can use their SMTP server in your C# application, simply use these settings and it should all work.
Hostname: smtp.gmail.com
Port: 587
Username: your_email#gmail.com
Password: ********
RequireSSL: true
Have a look at SmtpListener, I think it does what you want.
It isn't a standard email server which will receive new emails throught SMTP, store them on disk and allow you to retrieve them using POP.
SmtpListener will create a SMTP server that will receive email and allow you to react to any new email through code.
However, please note that you will have to configure it in your production environment like a real SMTP server, including MX DNS entries.
Related
Wonder if you can help please? I created an email notification system for windows app. This app is accessed via file server and citrix. It works perfectly using via file server and sends email notification using logged in users local outlook.
But when the user attempt to send notifications while accessing the same application via citrix it fails to run as we do not have the outlook access via citrix due to corporate policies.
We have been suggested to either request installation of outlook on citrix server (which will take a long time before it can be approved from top management) or re-write the code to access the local device outlook through citrix.
Does any one have any suggestion or example on how to proceed with such case?
Thank you very much for your help in advance.
You could use Smtp mail client:
System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
message.To.Add("shiraz#address.com");
message.Subject = "This is the Subject line";
message.From = new System.Net.Mail.MailAddress("BSingh#address.com");
message.Body = "This is the message body";
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("**yoursmtphost**");
smtp.Send(message);
I would recommend to use MailKit for email notifications since smtp client is obsolete
From MS site:
Important
We don't recommend that you use the SmtpClient class for new development because SmtpClient doesn't support many modern protocols. Use MailKit or other libraries instead. For more information, see SmtpClient shouldn't be used on GitHub.
I try to send emails with my dedicated office365 account but I have issues with subject encoding - all my special characters are replaced with "?".
Code I use is pretty simple and works fine with different test account at smtp-mail.outlook.com.
using (var mailMsg = new MailMessage(sender, recipient))
{
mailMsg.IsBodyHtml = true;
mailMsg.Subject = "Hello world żółćąź";
mailMsg.Body = body;
using (var smtpClient = new SmtpClient())
{
smtpClient.Credentials = new NetworkCredential("email", "password");
smtpClient.EnableSsl = true;
smtpClient.Host = "smtp.office365.com";
smtpClient.Port = 587;
await smtpClient.SendMailAsync(mailMsg);
}
}
I tried to set all possible subject encoding with no luck. Also converting subject string to Base64String also don't work. Also tried to set Content-Type header charset... All of the resolutions I found didn't help me. Maybe this is some specific SmtpClient issue realated only with office365?
And also setting the body encoding did not help
mailMsg.BodyEncoding = Encoding.UTF8;
I had the same issue with my company's account. Here are my findings so far:
It looks like the Office365 e-mail servers enabled the SMTPUTF8 extension a few months ago which changes the behavior of the System.Net.Mail.SmtpClient class into sending different SMTP commands and a different DATA payload.
In my case the message would always arrive fine when sent to another Office365 account but for other accounts we received e-mail bounce notices from the remote SMTP server which accepted the relayed e-mail message from Office365. The error was something like "Invalid data received, expected 7-bit-safe characters". I could thus imagine that the remote SMTP server from the OP might silently replace all characters outside the low 7-bit range with a question mark.
Sending through GMail (which also has the SMTPUTF8 extension active) had no problems.
So far I haven't debugged the SmtpClient reference sources yet to see what gets sent to the Office365 server. The root cause could thus either be that SmtpClient sends a good message which Office365 "corrupts" before relaying and which GMail sends on without issue; or SmtpClient builds a bad message / SMTP session which Office365 silently accepts and forwards to remote SMTP servers but which GMail accepts and fixes on the fly before relaying.
Either way, I pulled in the MailKit and MimeKit libraries using NuGet and use those instead to send my e-mails. These offer SMTP protocol logging to troubleshoot issues and appear to solve the stated problem by properly sending the SMTPUTF8 and 8BITMIME flags as defined in RFC 6531. It does take extra work to read configuration from the usual Web.config or App.config location but the libraries do the job.
If you want to keep using SmtpClient then you should either contact Microsoft (it's their service and their .NET Runtime), or run your own private SMTP server without the SMTPUTF8 extension which relays to remote servers. In the latter case SmtpClient should properly encode all headers and payload (though it does mean that you might be unable to use the International value for the DeliveryFormat property when you want to send to people with an internationalized e-mail address).
Set the encoding of the mail message so one that supports the characters you use, since the default is us-ascii:
mailMsg.BodyEncoding = Encoding.UTF8;
We had the same Issue with Office365 SMTP Server, using vmime library. We solved it by disabling SMTPUTF8, thus always encoding non-ascii characters.
As stated above by JBert, the same protocol works with GMail SMTP servers.
I tried to Send email from a Desktop app using SMTP sever but my network is secure and port is closed.
So, is there another way to send email like using Gmail api ?!
I use this code but doesn't work with me
public void Send_Mail(string HTMLBody, string MailTo)
{
MailMessage Mail = new MailMessage();
SmtpClient SmtpClient = new SmtpClient();
string MailSubject = "Subject;
string MailFrom = "from#xxxx.com";
Mail.Subject = MailSubject;
Mail.Body = HTMLBody;
Mail.To.Add(MailTo);
MailAddress From = new MailAddress(MailFrom);
Mail.From = From;
Mail.IsBodyHtml = true;
SmtpClient.Host = "host";
SmtpClient.Port = port;
SmtpClient.EnableSsl = true;
SmtpClient.Send(Mail);
}
If your network doesn't allow outbound connections to whatever port gmail uses (or restricts a particular protocol, or IP, etc), then there's nothing you can do. You would have to talk to the "network guys" to either remove this restriction for you or better yet, ask them to provide the local smtp server for you to use.
I've worked in a place where we had a similar problem. Desktop machines were not allowed to send emails, but servers could be permissioned to talk to an SMTP server.
What we ended up doing was writing a windows service that listened for messages placed on a queue (Tibco EMS in our case, but MSMQ would also do). The service took the messages from the queue and passed them onto the SMTP server is was permissioned to use.
It added an extra step, and process, to the system, but was enough to satisfy the compliance department.
Normally a "secure network" means that there is a firewall in place that restricts the traffic and only allows communication on certain ports like port 80 and maybe 8080.
Such networks (workplaces, shared office spaces, schools, eg.) usually have an outgoing SMTP server you could use. Alternatively you will need to use a server that can be contacted through the port(s) that are actually open or relay/tunneling the request through a third party.
I am trying to send 4 emails using my isp. (NOT JUNK MAIL, i send it to my address)
I send them one by one from a loop (as I build them). every message is 50kb-80kb
MailMessage mailmessage = new MailMessage();
mailmessage.To.Add(to);
mailmessage.From = new MailAddress(from, "From");
mailmessage.IsBodyHtml = true;
mailmessage.Priority = MailPriority.Normal;
mailmessage.Subject = subject;
mailmessage.Body = body;
SmtpClient smtpclient = new SmtpClient(server, 25); //use this PORT!
smtpclient.DeliveryMethod = SmtpDeliveryMethod.Network;
smtpclient.Credentials = new NetworkCredential(user, pass);
smtpclient.Send(mailmessage);
On last message I get this error:
Service not available, closing
transmission channel. The server
response was: Connection not accepted
at this time
UPDATE:
some times after this error , I can't send any email (using this server) even from other applications like outlook express, I get error:
An unknown error has occurred.
Account: 'MailServerAddress', Server:
'MailServerAddress'', Protocol: SMTP,
Server Response: '421 Connection not
accepted at this time', Port: 25,
Secure(SSL): No, Server Error: 421,
Error Number: 0x800CCC67
after about a minute, I can send again.
Always make sure your sender address is also a valid mailbox so bounce messages actually get back to you, many ISPs prohibit use of other (unregistered) sender addresses entirely. As pointed out in the comments by others, there is typically also rate limiting by the ISP so you'll have to fine-tune your sending code to the ISPs expectations, which can be tedious.
In general, sending emails is both art and science for some reason. If you're trying to use this for a production system, I can only suggest you use some service such as SendGrid or Mailgun. Even if your mail server accepts the messages, it might hit a limit on another ISPs mail server because most ISPs have certain limits and email routing is quite complicated. Also you might hit spam filters quickly. With my ISP, automated messages always to go spam in googlemail for whatever reason.
For development, Mailgun offers a two hundred emails per day for free which should be enough in the beginning. Also, SMTP is a very slow protocol so using their HTTP interface will save you some server time.
I had not exactly, but very similar issue here:
SMTP send email failure by SmtpClinet (SmarterEmail server)
The problem was that my local ISP was closing 25 port.
Have you tested some other ports, like 587?
I have an application that needs to send e-mails. Currently, this is what I am using:
System.Net.Mail.MailMessage MyMailMessage = new System.Net.Mail.MailMessage();
MyMailMessage.From = new System.Net.Mail.MailAddress(fromemail.Text);
MyMailMessage.To.Add(toemail.Text);
MyMailMessage.Subject = subject.Text;
MyMailMessage.Body = body.Text;
System.Net.Mail.SmtpClient SMTPServer = new System.Net.Mail.SmtpClient("smtp.gmail.com");
SMTPServer.Port = 587;
SMTPServer.Credentials = new System.Net.NetworkCredential("email", "password");
SMTPServer.EnableSsl = true;
SMTPServer.Send(MyMailMessage);
Is there a simple way to send an e-mail without having to login to a server? Thank you.
GMail's SMTP server always requires authentication. You may need to setup your own server to send email without authentication.
Configure an SMTP server into your local network (behind a firewall to avoid being a spam source) and use it directly. You can create one in IIS.
There are 2 ways to achieve this:
1) Use your local smtp server (e.g. one with IIS on Win2003/2008 server) and write messages to the local pickup queue). This is possible with minimal changes.
2) You need to resolve the target smtp server. For example when you want to send an email to somebody at msn.com, you'll need to get the MX record for msn.com, e.g. something like mx1.msn.com. You can then directly connect to this SMTP server and send your email to the (local) recipient. Note that there are no built-in ways to resolve the MX-host in .NET (in the sense there are no methods on the Dns class to accomplish this) - you need to do it "manually". Also most SMTP hosts will reject connections from home/residential IP addresses.
You need an SMTP server that does not require authentication, however to stop it being a SPAM server, it needs some other kind of protection like a firewall.