' Add EASendMail namespace
Imports EASendMail 

Module Module1 
    Sub Main() 
        Dim oMail As New SmtpMail("TryIt") 
        Dim oSmtp As New SmtpClient() 

        ' Set sender email address, please change it to yours
        oMail.From = "test@emailarchitect.net" 

        ' Set recipient email address, please change it to yours
        oMail.To = "support@emailarchitect.net" 

        ' Set email subject
        oMail.Subject = "test encrypted email" 

        ' Set email body
        oMail.TextBody = "this is a test email with email encryption (S/MIME)" 

        ' Your SMTP server address
        Dim oServer As New SmtpServer("smtp.emailarchitect.net") 

        ' User and password for ESMTP authentication, if your server doesn't require
        ' User authentication, please remove the following codes.
        oServer.User = "test@emailarchitect.net" 
        oServer.Password = "testpassword" 

        ' If your SMTP server requires SSL/TLS connection, please add this line
        ' oServer.ConnectType = SmtpConnectType.ConnectSSLAuto

        Try 

            ' Find certificate by email adddress in My Personal Store.
            ' Once the certificate is loaded to From, the email content
            ' will be signed automatically
            oMail.From.Certificate.FindSubject(oMail.From.Address, _ 
                Certificate.CertificateStoreLocation.CERT_SYSTEM_STORE_CURRENT_USER, _ 
                "My") 

        Catch exp As Exception 

            Console.WriteLine("No sign certificate found for <" + _ 
                oMail.From.Address + ">:" + exp.Message) 
        End Try 

       Dim count As Integer = oMail.To.Count 
        For i As Integer = 0 To count - 1 

            Dim oAddress As MailAddress = oMail.To(i) 
            Try 

                ' Find certificate by email adddress in My Other Peoples Store.
                ' The certificate can be also imported by *.cer file like this:
                ' oAddress.Certificate.Load("c:\encrypt1.cer")
                ' Once the certificate is loaded to MailAddress, the email content
                ' will be encrypted automatically

                oAddress.Certificate.FindSubject(oAddress.Address, _ 
                    Certificate.CertificateStoreLocation.CERT_SYSTEM_STORE_CURRENT_USER, _ 
                    "AddressBook") 

            Catch ep As Exception 

                Try 
                    oAddress.Certificate.FindSubject(oAddress.Address, _ 
                        Certificate.CertificateStoreLocation.CERT_SYSTEM_STORE_CURRENT_USER, _ 
                        "My") 

                Catch exp As Exception 

                    Console.WriteLine("No encryption certificate found for <" + _ 
                         oAddress.Address + ">:" + exp.Message) 
                End Try 
            End Try 
        Next 

        Try 

            Console.WriteLine("start to send encrypted email ...") 
            oSmtp.SendMail(oServer, oMail) 
            Console.WriteLine("email was sent successfully!") 

        Catch ep As Exception 

            Console.WriteLine("failed to send email with the following error:") 
            Console.WriteLine(ep.Message) 
        End Try 

    End Sub 
End Module