c# 4.0 - how to i SMTP with c# 4/.NET 4 to port 465/SSL (...

first, i've discovered through trial and error that c# 4/.NET 4 has some serious limitations which are to me unexplainable.

Microsoft is not supporting SSL over port 465 in c# 4/.NET 4.

Microsoft only supports SSL on 587 through "STARTTLS".

i need to use 465/SSL because my mail server hMailServer does not support "STARTTLS".

i had hoped to use c# 4/.NET 4 out of the box ... i do not want to purchase any third party solutions.

what i would like to do is to craft my own solution for SMTP using SSL on port 465.

i'm guessing that i may have to use c# unmanaged code to make this happen.

any ideas?, please & thank you. rgds/gerry

References:

"configuring SSL confusion...", hMailServer forum thread.

MSDN: "SmtpClient.EnableSsl Property":
"An alternate connection method is where an SSL session is established up front before any protocol commands are sent. This connection method is sometimes called SMTP/SSL, SMTP over SSL, or SMTPS and by default uses port 465. This alternate connection method using SSL is not currently supported."

P.S.: i searched SO and Google and can find nothing directly relevant.

f you can, and if it still works ("This API is now obsolete"), you should be able to use SMTPS (SMTP with up-front SSL/TLS) using System.Web.Mail.MailMessage:

System.Web.Mail.MailMessage mailMsg = new System.Web.Mail.MailMessage();
// ...
mailMsg.Fields.Add
            ("http://schemas.microsoft.com/cdo/configuration/smtpusessl",
                 true);

Of course, the fact that this API is now obsolete in .Net 4 is not ideal. It probably still works in practice.

Failing that, you may have to rely on 3rd-part libraries or something like stunnel.