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Trying to send SMTP email - connection refused

I am trying to send an email to MailTrap.io its a free smtp portal for checking the email but im getting the following error.
I am using MailKit to send the email
https://mailtrap.io
public async Task SendEmailAsync(string email, string subject, string message)
{
try
{
var emailMessage = new MimeMessage();
emailMessage.From.Add(new MailboxAddress("David", "davidnoreply#gmail.com"));
emailMessage.To.Add(new MailboxAddress("", email));
emailMessage.Subject = subject;
emailMessage.Body = new TextPart("HTML") { Text = message };
using (var client = new SmtpClient())
{
client.LocalDomain = "http://localhost:52101";
await client.ConnectAsync("smtp.mailtrap.io", 584, true);
client.Authenticate("16729fdfa173b4", "0e6de61c67b069");
client.Send(emailMessage);
//await client.emailMessage(emailMessage).ConfigureAwait(false);
//await client.DisconnectAsync(true).ConfigureAwait(false);
}
}
catch (Exception ex)
{
// TODO: handle exception
throw new InvalidOperationException(ex.Message);
}
}
But the following error presents itself I have tried on port 25 but then i get an error about ssl.
No connection could be made because the target machine actively
refused it. 127.0.0.1:25
If I change it to port 25 I get the following.
An error occurred while attempting to establish an SSL or TLS connection.
This usually means that the SSL certificate presented by the server is not trusted by the system for one or more of
the following reasons:
1. The server is using a self-signed certificate which cannot be verified.
2. The local system is missing a Root or Intermediate certificate needed to verify the server's certificate.
3. A Certificate Authority CRL server for one or more of the certificates in the chain is temporarily unavailable.
4. The certificate presented by the server is expired or invalid.
Another possibility is that you are trying to connect to a port which does not support SSL/TLS.
It is also possible that the set of SSL/TLS protocols supported by the client and server do not match.
See https://github.com/jstedfast/MailKit/blob/master/FAQ.md#SslHandshakeException for possible solutions.
Edit 2
I removed the ssl but stil the same error above.
public async Task SendEmailAsync(string email, string subject, string message)
{
try
{
var emailMessage = new MimeMessage();
emailMessage.From.Add(new MailboxAddress("David", "david#gmail.com"));
emailMessage.To.Add(new MailboxAddress("", email));
emailMessage.Subject = subject;
emailMessage.Body = new TextPart("HTML") { Text = message };
using (var client = new SmtpClient())
{
await client.ConnectAsync("smtp.mailtrap.io", 25, true);
client.Authenticate("16729fdfa173b4", "0e6de61c67b069");
client.Send(emailMessage);
//await client.emailMessage(emailMessage).ConfigureAwait(false);
//await client.DisconnectAsync(true).ConfigureAwait(false);
}
}
catch (Exception ex)
{
// TODO: handle exception
throw new InvalidOperationException(ex.Message);
}
}

Emails not sending with Mailkit or .net smtp client

The native MVC UserManager.sendasync works great. But when i instantiate an Email service and try to send an email ... no dice. I made a php script to send the email. Works beatuifully super easy. I also tried downloading and using Mailkit... no dice. Im not sure what to do here. No error message
var mimeMessage = new MimeMessage();
mimeMessage.From.Add(new MailboxAddress("System", "system#my.hypertarget.io"));
mimeMessage.To.Add(new MailboxAddress("Jason", "unblockgames#gmail.com"));
mimeMessage.Subject = "Test";
mimeMessage.Body = new TextPart("plain"){Text = message};
using (var client = new SmtpClient())
{
// For demo-purposes, accept all SSL certificates (in case the server supports STARTTLS)
client.ServerCertificateValidationCallback = (s, c, h, e) => true;
client.Connect("relay-hosting.secureserver.net", 25, false);
client.Capabilities &= ~SmtpCapabilities.Pipelining;
client.Send(mimeMessage);
client.Disconnect(true);
}

AE.Net.Mail not able to connect to outlook.office365.com IMAP

I am finding that I am unable to connect to outlook.office365.com's IMAP server using AE.Net.Mail. The code is very simple:
this._imapClient = new ImapClient(imapServer, username, password, AE.Net.Mail.AuthMethods.Login, port, enableSSL)
I find that I can connect to GMail with no issues, but office365 outlook will not connect, I keep getting timeouts. I've verified the IMAP settings by putting them in to Outlook and in to Thunderbird.
Has anyone else had trouble connecting AE.Net.Mail to Office365's IMAP server?

AE.Net.Mail is quite buggy and has not seen any development in over a year last I checked. I would recommend using MailKit instead.
I just confirmed that MailKit works with Office365.com with the following code snippet:
using (var client = new ImapClient ()) {
client.Connect ("outlook.office365.com", 993, true);
client.Authenticate ("username", "password");
// get the unread messages
var uids = client.Inbox.Search (SearchQuery.NotSeen);
foreach (var uid in uids) {
var message = client.Inbox.GetMessage (uid);
}
client.Disconnect (true);
}
Hope that helps.

Found I am able to connect by increasing the timeouts:
_imapClient.ServerTimeout = 120000;
_imapClient.IdleTimeout = 120000;
_imapClient.Connect(_imapServer, _port, _enableSSL, false);
_imapClient.Login(_username, _password);
_imapClient.SelectMailbox("Inbox");

C# - TLS / SSL Websockets using fleck

Im trying to make a TLS/SSL websocket connection using Fleck lib.
https://github.com/statianzo/Fleck (0.9.8.25)
now i got the server startet .
but when a client connects i get the following message.
28-02-2014 19:16:15 [Info] Server started at wss://localhost:8081
28-02-2014 19:18:51 [Debug] Client connected from 127.0.0.1:62543
28-02-2014 19:18:51 [Debug] Authenticating Secure Connection
28-02-2014 19:18:52 [Debug] 0 bytes read. Closing.
anybody got an idea of what im doing wrong ?
Browser: Chrome, version : 33.0.1750.117
// sample code.
FleckLog.Level = LogLevel.Debug;
var allSockets = new List<IWebSocketConnection>();
var server = new WebSocketServer("wss://localhost:8081");
server.Certificate = new X509Certificate2(#"CRT.pfx", "Pwd");
server.Start(socket =>
{
socket.OnOpen = () =>
{
Console.WriteLine("Open!");
allSockets.Add(socket);
};
socket.OnClose = () =>
{
Console.WriteLine("Close!");
allSockets.Remove(socket);
};
socket.OnMessage = message =>
{
foreach (var user in allSockets.ToList())
{
if(user.ConnectionInfo.Id != socket.ConnectionInfo.Id){
user.Send(message);
}
}
};
});
var input = Console.ReadLine();
while (input != "exit")
{
foreach (var socket in allSockets.ToList())
{
socket.Send(input);
}
input = Console.ReadLine();
}

Is certificate signed by a browser trusted CA? If not, the web page you are opening with Chrome has to be under HTTPS so you can be prompted to accept the certificate, otherwise the connection will fail.
If even doing that does not work, please try with WebSocketListener and tell me which error you get if any.
Some issues I found debugging WSS:
Remember to change the port number to a one different to the one you used for not secure connections. Some browsers get confused if suddenly a port becomes secure or viceversa.
Remember to use the hostname indicated in the certificate to connect and not the IP.
If you are using a self-signed certificate, use it for HTTPS so you can see the dialog for accepting that certificate. When accessing via WSS:// there is not certificate acceptance dialog, it will just fail to connect.
Try with a self-signed certificate as well and see if it works.

Using StartTLS with LDAP from System.DirectoryServices

I'm trying to connect to an LDAP server which requires StartTLS, but having no luck - whenever I use either the SessionOptions.StartTransportLayerSecurity(..) or set SessionOptions.SecureSocketLayer to true, I get exceptions.
Here's the code I'm using:
using (var connection = new LdapConnection(new LdapDirectoryIdentifier(config.LdapServer, config.Port, false, false)))
{
connection.SessionOptions.ProtocolVersion = 3;
connection.Credential = new NetworkCredential(config.BindDN, config.BindPassword);
connection.SessionOptions.VerifyServerCertificate += (conn, cert) => {return true;};
connection.AuthType = AuthType.Basic;
//connection.SessionOptions.SecureSocketLayer = true;
connection.SessionOptions.StartTransportLayerSecurity(null); // throws here, same if done after bind.
connection.Bind();
... do stuff with connection
}
The resulting exception is "TlsOperationException: An unspecified error occurred", which happens when invoking the StartTransportLayerSecurity method.
I've tested the code against both and OpenLDAP server and Active Directory, but neither works.
Does anyone know how to get StartTLS working with System.DirectoryServices?

There used to be a fair amount of subtle LDAP stack incompatibilities in the wild, which could still apply to the potentially legacy scenario your customer might be using.
The following are the most commonly encountered issues regarding incompatibilities between OpenLDAP and Microsoft's LDAP stack (I'll amend and/or replace these links once more info is available):
The OpenLDAP StartTLS issues (ITS#3037) (summarized in On getting OpenLDAP and Windows LDAP to interop) have triggered a respective hotfix:
You cannot send Start TLS requests from a computer that is running Windows Server 2003 or Windows XP or Windows Vista to a server that is running OpenLDAP Software
An extended operation that is sent to an LDAP server by API over the LDAP service causes a protocol error
Obviously, updating either OpenLDAP and/or Windows (ideally both of course) should remedy these issues, if they turn out to be the culprit here.
Good luck!

Please read this topic:
Binding over a TLS/SSL Encrypted Connection
Example 19. Binding to an ADAM instance on secure port 50001 using Basic authentication and SSL/TLS
string hostNameAndSSLPort = "sea-dc-02.fabrikam.com:50001";
string userName = "cn=User1,cn=AdamUsers,cn=ap1,dc=fabrikam,dc=com";
string password = "adamPassword01!";
// establish a connection
LdapConnection connection = new LdapConnection(hostNameAndSSLPort);
// create an LdapSessionOptions object to configure session
// settings on the connection.
LdapSessionOptions options = connection.SessionOptions;
options.ProtocolVersion = 3;
options.SecureSocketLayer = true;
connection.AuthType = AuthType.Basic;
NetworkCredential credential =
new NetworkCredential(userName, password);
connection.Credential = credential;
try
{
connection.Bind();
Console.WriteLine("\nUser account {0} validated using " +
"ssl.", userName);
if (options.SecureSocketLayer == true)
{
Console.WriteLine("SSL for encryption is enabled\nSSL information:\n" +
"\tcipher strength: {0}\n" +
"\texchange strength: {1}\n" +
"\tprotocol: {2}\n" +
"\thash strength: {3}\n" +
"\talgorithm: {4}\n",
options.SslInformation.CipherStrength,
options.SslInformation.ExchangeStrength,
options.SslInformation.Protocol,
options.SslInformation.HashStrength,
options.SslInformation.AlgorithmIdentifier);
}
}
catch (LdapException e)
{
Console.WriteLine("\nCredential validation for User " +
"account {0} using ssl failed\n" +
"LdapException: {1}", userName, e.Message);
}
catch (DirectoryOperationException e)
{
Console.WriteLine("\nCredential validation for User " +
"account {0} using ssl failed\n" +
"DirectoryOperationException: {1}", userName, e.Message);
}
And the next example show "How to use TLS to authenticate and perform a task"
string hostOrDomainName = "fabrikam.com";
string userName = "user1";
string password = "password1";
// establish a connection to the directory
LdapConnection connection = new LdapConnection(hostOrDomainName);
NetworkCredential credential =
new NetworkCredential(userName, password, domainName);
connection.Credential = credential;
connection.AuthType = AuthType.Basic;
LdapSessionOptions options = connection.SessionOptions;
options.ProtocolVersion = 3;
try
{
options.StartTransportLayerSecurity(null);
Console.WriteLine("TLS started.\n");
}
catch (Exception e)
{
Console.WriteLine("Start TLS failed with {0}",
e.Message);
return;
}
try
{
connection.Bind();
Console.WriteLine("Bind succeeded using basic " +
"authentication and SSL.\n");
Console.WriteLine("Complete another task over " +
"this SSL connection");
TestTask(hostName);
}
catch (LdapException e)
{
Console.WriteLine(e.Message);
}
try
{
options.StopTransportLayerSecurity();
Console.WriteLine("Stop TLS succeeded\n");
}
catch (Exception e)
{
Console.WriteLine("Stop TLS failed with {0}", e.Message);
}
Console.WriteLine("Switching to negotiate auth type");
connection.AuthType = AuthType.Negotiate;
Console.WriteLine("\nRe-binding to the directory");
connection.Bind();
// complete some action over this non-SSL connection
// note, because Negotiate was used, the bind request
// is secure.
// run a task using this new binding
TestTask(hostName);

After a bit more work on this issue I found that I was running up against a couple of issues:
There was a bug in the code where the port number was being incorrectly changed to the SSL port (636) when connecting to AD in our test suite (doh!).
The OpenLDAP test server (that was a replica of our customers) was using openldap-2.4.18 - which has known issues with StartTLS.
After applying a patch to OpenLDAP (as discussed here - http://www.openldap.org/lists/openldap-bugs/200405/msg00096.html) we were able to fix #2 - at which point we started getting a different error "A local error occurred".
Though originally we had this code:
connection.SessionOptions.VerifyServerCertificate
+= (conn, cert) => {return true;};
We had removed it while testing, and because the OpenLDAP server was using a self-signed cert, that was not in a trusted store. Re-introducing that callback resolved this issue, though we now make it a configurable option i.e. "Verify Server Certificate Y/N" so customers need to opt into skipping the check (mostly for our QA team to use).
Thanks Steffen for pointing me in the direction of OpenLDAP versions which lead me to this solution.