Which is the best managed .NET e-mail component with support for S/MIME?

Question

I need a replacement for System.Net.Mail.MailMessage that is able to send signed and/or encrypted e-mails.

Is there an open source library covering that?

Or do you have some experiences with some of those:

• Chilkat Mail
• Easymail

• Dart Mail for .NET

• You got more?

Answer 1

It seems like you can in fact send S/MIME encrypted emails using the BCL of .NET. It requires a bit of a hack (not too bad however), but you could wrap the solution easy enough... See this MSDN forum thread and possibly also this one. Note that an example is additionally provided for Rebex Secure Mail, a commercial product, if you're having no luck with the BCL solution. Saying that, I would definitely recommend using the solution provided in the System.Net namespace if at all possible, despite requiring a bit of custom configuration.

Answer 2

MIMEBlackbox is the most feature-rich component set for MIME, S/MIME and PGP/MIME.