Sending emails from C# Application

[AlwynJ-B]

I have a BTConnect email address and am developing a small Dot.Net App to send emails to members of a small charity of which I am treasurer.  I have set the App up to use the same settings that I used in Windows Live Mail for connecting to BTConnect, but cannot get it to work.  Are there any special settings that BTConnect needs?  Advice please!

[Bobby]

Hey AlwynJ-B,

I've provided a link below with the server settings required for any @btconnect.com email accounts. The instructions below are related to setup on Outlook, but the 'Quick Settings' up top are the details that we're after. I believe Windows Live Mail is no longer supported but you should still be able to authenticate with the mail server regardless.

How to set up Office 365 email | BT Business

Thanks, Bobby

[AlwynJ-B]

Hi Bobby,

Many thanks for the link.  It pointed out that for out-going emails I need to invoke TLS.  C# contains a SmtpClient class which allows the developer to set values including whether SSL is to be used, but makes no mention directly of TLS.  The class does allow for a 'ClientCertificates' property to be set and this involves an X509Certificates Collection.  On looking up X509Certifcates I see that it involves encryption of messages between the user and the Server (BtConnect in my case), and that TLS depends upon such a certificate.  It seems that I will have to obtain a certificate from Brithish Telecom or use a different server without needing TLS. 

I assume 'Windows Live Mail' and other Client Apps have such a certificate built-in, or a built-in means of obtaining it because, when stting the BtConnect properties in Windows Live Mail, there is no mention of TLS. 

See https://en.wikipedia.org/wiki/X.509

AlwynJ-B