Formerly, I used my server as mail host and was sending emails via my own host. Now, I use Yandex as my mail server. I'm trying to send emails via Yandex SMTP. However, I could not achieve it. I get "the operation has timed out" message every time. I'm able to send & receive email with the same settings when I use Thunderbird. Hence, there is no issue with the account. I appreciate your guidance. You can see my code below:
EmailCredentials credentials = new EmailCredentials();
credentials.Domain = "domain.com";
credentials.SMTPUser = "email#domain.com";
credentials.SMTPPassword = "password";
int SmtpPort = 465;
string SmtpServer = "smtp.yandex.com";
System.Net.Mail.MailAddress sender = new System.Net.Mail.MailAddress(senderMail, senderName, System.Text.Encoding.UTF8);
System.Net.Mail.MailAddress recipient = new System.Net.Mail.MailAddress(recipientEmail, recipientName, System.Text.Encoding.UTF8);
System.Net.Mail.MailMessage email = new System.Net.Mail.MailMessage(sender, recipient);
email.BodyEncoding = System.Text.Encoding.UTF8;
email.SubjectEncoding = System.Text.Encoding.UTF8;
System.Net.Mail.AlternateView plainView = System.Net.Mail.AlternateView.CreateAlternateViewFromString(System.Text.RegularExpressions.Regex.Replace(mailBody, #"<(.|\n)*?>", string.Empty), null, MediaTypeNames.Text.Plain);
System.Net.Mail.AlternateView htmlView = System.Net.Mail.AlternateView.CreateAlternateViewFromString(mailBody, null, MediaTypeNames.Text.Html);
email.AlternateViews.Clear();
email.AlternateViews.Add(plainView);
email.AlternateViews.Add(htmlView);
email.Subject = mailTitle;
System.Net.Mail.SmtpClient SMTP = new System.Net.Mail.SmtpClient();
SMTP.Host = SmtpServer;
SMTP.Port = SmtpPort;
SMTP.EnableSsl = true;
SMTP.Credentials = new System.Net.NetworkCredential(credentials.SMTPUser, credentials.SMTPPassword);
SMTP.Send(email);
After so many trials & errors, I have found how to make it work. I have made the following changes on the code posted in the question:
Set SmtpPort = 587
Added the following 2 lines of code:
SMTP.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
SMTP.UseDefaultCredentials = false;
Additional note:
I use Azure server. I realized later that I did not configure the smtp endpoint for port 465. That being said, I had to add the 2 lines of code above in order to make email delivery work, just changing the port was not enough. My point is it is worth to check the defined ports on Azure and firewall before doing anything further.
I was able to make my code work by getting help from #Uwe and also #Dima-Babich, #Rail who posted on the following page Yandex smtp settings with ssl
. Hence, I think credits to answer this question should go to them.
Try using port 25 instead of 465 specified in Yandex help. I found this info on https://habrahabr.ru/post/237899/. They mentioned that it might be due to the fact that explicit SSL mode was implemented in the SmtpClient. Then port 25 is used for establishing connection in unencrypted mode and after that, protected mode is switched on.
I had the same problem.
I solved it by going to the Yandex mail, and then change some settings.
Go to:
1- Settings.
2- Email clients.
3- Set selected POP3 setting that is all.
Related
I'm trying to set up some code to send email via Office 365's authenticated SMTP service:
var _mailServer = new SmtpClient();
_mailServer.UseDefaultCredentials = false;
_mailServer.Credentials = new NetworkCredential("test.user#mydomain.com", "password");
_mailServer.Host = "smtp.office365.com";
_mailServer.TargetName = "STARTTLS/smtp.office365.com"; // same behaviour if this lien is removed
_mailServer.Port = 587;
_mailServer.EnableSsl = true;
var eml = new MailMessage();
eml.Sender = new MailAddress("test.user#mydomain.com");
eml.From = eml.Sender;
eml.to = new MailAddress("test.recipient#anotherdomain.com");
eml.Subject = "Test message";
eml.Body = "Test message body";
_mailServer.Send(eml);
This doesn't appear to be working, and I'm seeing an exception:
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.57 SMTP; Client was not authenticated to send anonymous mail during MAIL FROM
at System.Net.Mail.MailCommand.Send(SmtpConnection conn, Byte[] command, String from)
at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
I've tried enabling network tracing and it appears that secure communications are established (for example, I see a line in the log for the "STARTTLS" command, and later there's a line in the log "Remote certificate was verified as valid by the user.", and the following Send() and Receive() data is not readable as plain text, and doesn't appear to contain any TLS/SSH panics)
I can use the very same email address and password to log on to http://portal.office.com/ and use the Outlook email web mail to send and read email, so what might be causing the authentication to fail when sending email programmatically?
Is there any way to additionally debug the encrypted stream?
In my case after I tried all this suggestion without luck, I contacted Microsoft support, and their suggestion was to simply change the password.
This fixed my issue.
Note that the password wasn't expired, because I logged on office365 with success, however the reset solved the issue.
Lesson learned: don't trust the Office 365 password expiration date, in my case the password would be expired after 1-2 months, but it wasn't working.
This leaded me to investigate in my code and only after a lot of time I realized that the problem was in the Office365 password that was "corrupted" or "prematurely expired".
Don't forget every 3 months to "refresh" the password.
To aid in debugging, try temporarily switching to MailKit and using a code snippet such as the following:
using System;
using MailKit.Net.Smtp;
using MailKit.Security;
using MailKit;
using MimeKit;
namespace TestClient {
class Program
{
public static void Main (string[] args)
{
var message = new MimeMessage ();
message.From.Add (new MailboxAddress ("", "test.user#mydomain.com"));
message.To.Add (new MailboxAddress ("", "test.recipient#anotherdomain.com"));
message.Subject = "Test message";
message.Body = new TextPart ("plain") { Text = "This is the message body." };
using (var client = new SmtpClient (new ProtocolLogger ("smtp.log"))) {
client.Connect ("smtp.office365.com", 587, SecureSocketOptions.StartTls);
client.Authenticate ("test.user#mydomain.com", "password");
client.Send (message);
client.Disconnect (true);
}
}
}
}
This will log the entire transaction to a file called "smtp.log" which you can then read through and see where things might be going wrong.
Note that smtp.log will likely contain an AUTH LOGIN command followed by a few commands that are base64 encoded (these are your user/pass), so if you share the log, be sure to scrub those lines.
I would expect this to have the same error as you are seeing with System.Net.Mail, but it will help you see what is going on.
Assuming it fails (and I expect it will), try changing to SecureSocketOptions.None and/or try commenting out the Authenticate().
See how that changes the error you are seeing.
Be sure you're using the actual office365 email address for the account. You can find it by clicking on the profile button in Outlook365. I wrestled with authentication until I realized the email address I was trying to use for authentication wasn't the actual mailbox email account. The actual account email may have the form of: account#company.onmicrosoft.com.
We got ours working by converting the mailboxes (from address) from "shared" to "regular". Before this change, my application quit sending email when we migrated from Gmail to Office 365. No other code changes were required, besides setting the host to smtp.office365.com.
Please check below code I have tested to send email using Exchange Online:
MailMessage msg = new MailMessage();
msg.To.Add(new MailAddress("YourEmail#hotmail.com", "XXXX"));
msg.From = new MailAddress("XXX#msdnofficedev.onmicrosoft.com", "XXX");
msg.Subject = "This is a Test Mail";
msg.Body = "This is a test message using Exchange OnLine";
msg.IsBodyHtml = true;
SmtpClient client = new SmtpClient();
client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential("XXX#msdnofficedev.onmicrosoft.com", "YourPassword");
client.Port = 587; // You can use Port 25 if 587 is blocked
client.Host = "smtp.office365.com";
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.EnableSsl = true;
try
{
client.Send(msg);
}
catch (Exception ex)
{
}
Port (587) was defined for message submission. Although port 587 doesn't mandate requiring STARTTLS, the use of port 587 became popular around the same time as the realisation that SSL/TLS encryption of communications between clients and servers was an important security and privacy issue.
In my case my problem was not related to the code but something to do with the Exchange mailbox. Not sure why but this solved my problem:
Go to the exchange settings for that user's mailbox and access Mail Delegation
Under Send As, remove NT AUTHORITY\SELF and then add the user's account.
This gives permissions to the user to send emails on behalf of himself. In theory NT AUTHORITY\SELF should be doing the same thing but for some reason that did not work.
Source: http://edudotnet.blogspot.com.mt/2014/02/smtp-microsoft-office-365-net-smtp.html
I got this same error while testing, using my own domain email account during development. The issue for me seemed related to the MFA (Multi Factor Authentication) that's enabled on my account. Switching to an account without MFA resolved the issue.
I had this issue since someone had enabled Security defaults in Azure.
This disables SMTP/Basic authentication. It's clearly stated in the documentation, but it's not evident by the error message, and you have to have access to the account to find out.
https://learn.microsoft.com/en-us/azure/active-directory/fundamentals/concept-fundamentals-security-defaults
It's possible to enable it per account.
https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission
You need change the credentials function. Here is the substitution you need to make:
change
-*_mailServer.Credentials = new NetworkCredential("test.user#mydomain.com", "password");*
for this
-*_mailServer.Credentials = new NetworkCredential("test.user#mydomain.com", "password", "domain");*
In my case, password was expired.I just reset password and its started working again
I use the following code to send email.Sometimes it works fine and some time it generate error .
Is there any better code to send emails.And one more thing is it necessary to provide password for sending mail.
using System.Net.Mail;
public void SendEmail()
{
MailMessage mail = new MailMessage();
mail.To.Add("sales#ojhatraders.com");
mail.From = new MailAddress("ojhatraderscustomer#gmail.com");
mail.Subject = "Contact Us Enquiry";
string Body = "<b>From:<b>" + mail.From + "<br/>" + "Your Query Recived "+"<br/>"+"Name"+nameTextBox.Text+"<br/>"+"Mobile:"+mobileTextBox.Text+"<br/>"
+"Email:"+emailTextBox.Text+"<br/>"+"Query:"+queryTextBox.Text;
mail.Body = Body;
mail.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient();
smtp.Host = "smtp.gmail.com"; //Or Your SMTP Server Address
smtp.Credentials = new System.Net.NetworkCredential("sample#gmail.com", "passsword");//Or your Smtp Email ID and Password
smtp.EnableSsl = true;
smtp.Send(mail);
}
Please provide some useful suggestion and better code.
Have you tried adding
smtp.Port = 587;
The best bet to keep your credentials secret is having an SMTP Server running that accepts anonymous referrers. With this criteria met, credentials aren't required with anonymous requests. There are fewer and fewer mail services allowing anonymous requests, while it used to be rampant < 10 years ago. Now most SMTP services require valid username and password credentials, some even network domain credentials.
Error
Without informing us with the error that your code generates, we can't really help solving that issue. You should check the recommended smtp-port. From Google support websuite:
If you tried configuring your SMTP server on port 465 (with SSL) and port 587 (with TLS), but are still having trouble sending mail, try configuring your SMTP to use port 25 (with SSL).
'Better' code
Sending mails are quite obvious in ASP.NET so 'better' code to send mails is more an opinion rather than a fact. However, I should split things up a little bit from an architectural point of view. This will improve code quality and reduce duplicate code.
Things you should consider do to make this code 'better'.
Make use of a stringbuilder to build your mail content and inject it into mailtemplate
Make a separate class 'Email' with e.g. default constructor, Send() and GetTemplate() method
Specify settings for SMTP in your web.config
That way you can make and send your e-mail from anywhere in your application in a few lines. Some example code from one of my applications:
var content = new StringBuilder();
content.Append("Name: " + contactForm.Name + "<br/>");
content.Append("Email: " + contactForm.Name + "<br/>");
content.Append("Message: " + contactForm.Name + "<br/>");
//Email constructor accepts two arguments: the content and the name of the template
var mail = new Email(content, "mailTemplateName")
mail.Send("mymail#domain.be", "recipient#gmail.com", "Subject of the mail")
Try including a port for your SMTP. Ones that are typically used are 25, 465, and 587. I usually use 25 without issues and you can also use 465 for ssl. I also usually set UseDefaultCredentials to false:
SmtpClient smtp = new SmtpClient();
smtp.Port = 25;
smtp.UseDefaultCredentials = false;
Also, you might want to dispose of your messages after you've used them. It's good practice and is safer for performance and cost.
using (smtp as IDisposable)
{
smtp.Send(yourEmail);
yourEmail.Dispose();
}
All in all, pretty open ended question. Hope this helps, but be a little more specific so you can get better help next time
Please can some one help me out whether the correct port for sending email from an gmail account is 25 ,465 or 587. I checked on some forms it says that C# classes does not support sending email using SSL it uses TSL and the port used for TSL is 587. IS it correct? I am confused.
Gmail usually works with Port Number 587 in .net Application.
Check the following Example Code sample
System.Net.Mail.SmtpClient SmtpClientObject = new System.Net.Mail.SmtpClient();
SmtpClientObject.UseDefaultCredentials = false;
SmtpClientObject.Credentials = new System.Net.NetworkCredential("MyUserName#gmail.com", "myPassword");
SmtpClientObject.Host = "smtp.gmail.com";
SmtpClientObject.Port = 587;
SmtpClientObject.EnableSsl = true;
SmtpClientObject.Send("MyUserName#gmail.com", "YourUserName#gmail.com", "TestSubject", "MessageBody");
I have a for loop which calls some code sending emails. I get the following run-time error:
Service not available, closing transmission channel. The server
response was: 4.4.2 Message submission rate for this client has
exceeded the configured limit
After googling around it appears to be related to the "set-receiveconnector", possible for exchange server? Could anyone advise how I can fix this?
the code:
var mail = new MailMessage();
var smtpServer = new SmtpClient(SMTPServer);
mail.From = new MailAddress(fromAddress);
mail.To.Add(toAddress);
mail.Subject = title;
mail.IsBodyHtml = isHTML;
mail.Body = message;
if(attach != null) mail.Attachments.Add(attach);
smtpServer.Port = xxx
smtpServer.UseDefaultCredentials = false;
smtpServer.Credentials = new NetworkCredential(SMTPUser, SMTPPassword);
smtpServer.EnableSsl = true;
smtpServer.Send(mail); //Error occurs here
Rather then sending the emails directly can you use a pickup folder?
SmtpMail.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
that way you just dump the messages in to the folder and let exchange send them when its ready, this way if your user can only send say 3 per minute exchange should send 3 then on the next pass send another 3 and so on.
I resolved this problem on my system by using the correct port. The way exchange had been set up meant that SSL = TRUE, Port = 587 produced this error. If I changed it to use Port 25, then everything worked just fine. So check with your sys admins this may help!
We fixed this from the Exchange side by setting the receive connector(s) to allow more than 5 messages at a time, eg:
Get-ExchangeServer | Set-ReceiveConnector "My Receive Connector" -Messageratelimit 20
I'm trying to send an email message using the .NET MailMessage class which can also have the return-path header added so that any bounces come back to a different email address. Code is below:
MailMessage mm = new MailMessage(
new MailAddress(string.Format("{0}<{1}>", email.FromName, email.FromEmail)),
new MailAddress(emailTo));
mm.Subject = ReplaceValues(email.Subject, nameValues);
mm.ReplyTo = new MailAddress(string.Format("{0}<{1}>", email.FromName, email.FromEmail));
mm.Headers.Add("Return-Path", ReturnEmail);
// Set the email html and plain text
// Removed because it is unneccsary for this example
// Now setup the smtp server
SmtpClient smtp = new SmtpClient();
smtp.Host = SmtpServer;
smtp.DeliveryMethod = SmtpDeliveryMethod.PickupDirectoryFromIis;
if (SmtpUsername.Length > 0)
{
System.Net.NetworkCredential theCredential =
new System.Net.NetworkCredential(SmtpUsername, SmtpPassword);
smtp.Credentials = theCredential;
}
smtp.Send(mm);
Whenever I check the email that was sent I check the header and it always seems to be missing return-path. Is there something I am missing to configure this correctly? As I said above I'm using the standard Virtual Mail Server on my development machine (XP) however it will run on Windows 2003 eventually.
Has anyone got any ideas why it isn't coming through?
The Return-Path is set based on the SMTP MAIL FROM Envelope. You can use the Sender property to do such a thing.
Another discussion on a related issue you will have sooner or later: How can you set the SMTP envelope MAIL FROM using System.Net.Mail?
And btw, if you use SmtpDeliveryMethod.PickupDirectoryFromIis, the Sender property is not used as a MAIL FROM; you have to use Network as a delivery method to keep this value.
I did not find any workaround for this issue.
PickupDirectoryFromIis, Sender property and SMTP MAIL FROM envelope