使用c＃.net使用证书签署电子邮件

Question

I am trying to send email with "From Certificate". I am using Framework 4.0, and in C# X509Certificates class.

SmtpClient sc = new SmtpClient(mSMTPServer, mSMTPPort);
sc.EnableSsl = true;
sc.ClientCertificates.Add(new X509Certificate(certificatePath, certPassword)); 
sc.Send(mail);

Problem I am facing is certificate is not attached or signed with email "from" part. Can any one help me please, how I signed from part of email using C#.NET and Framework 4.0?

Answer 1

UPDATED: Look at this link:

http://www.codeproject.com/Articles/41727/An-S-MIME-Library-for-sending-and-Signed-Encrypted

For only sign, pass the parameter to encrypt as null.

Answer 2

I'd recommend taking a look at MimeKit which you can use to digitally sign your email messages.

Then once you have a signed email, you can send it using MailKit 's SmtpClient class which is very similar to System.Net.Mail.SmtpClient.

System.Net.Mail.SmtpClient.ClientCertificates are not used for signing the message, they are ONLY used for authenticating with the server via SSL.