Select Encryption Algorithm with SMTP Encrypted Email

Demonstrates how to select the encryption algorithm and strength (key size) when sending encrypted email.

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//  The mailman object is used for sending and receiving email.
Chilkat.MailMan mailman = new Chilkat.MailMan();

//  Any string argument automatically begins the 30-day trial.
bool success;
success = mailman.UnlockComponent("30-day trial");
if (success != true) {
    MessageBox.Show("Component unlock failed");
    return;
}

//  Set the SMTP server.
mailman.SmtpHost = "smtp.comcast.net";

//  Create a new email object
Chilkat.Email email = new Chilkat.Email();

email.Subject = "This email is encrypted";
email.Body = "This is a digitally encrypted mail";
email.From = "Chilkat Support <support@chilkatsoft.com>";
email.AddTo("Chilkat Admin","admin@chilkatsoft.com");

//  In this example, we've already installed the certificate for "admin@chilkatsoft.com"
//  in the current user's personal certificate store.
//  If the email.SendEncrypted property is set, Chilkat will
//  automatically search for and use the first non-expired certificate
//  matching the recipient's email address.  Chilkat searches
//  the Current User's Personal certificate store, as well
//  as the Local Machine's Personal certificate store.
//  Run certmgr.msc to view the certs in the Current User's
//  certificate store.
email.SendEncrypted = true;

//  Use the CSP object to select an encryption algorithm:
Chilkat.Csp csp = new Chilkat.Csp();
//  Make sure we're using the enhanced provider, which provides
//  access to stronger algorithms.
csp.SetProviderMicrosoftEnhanced();

//  Select 168-bit 3DES (i.e. 192-bit DES if you include the parity bits)
csp.SetEncryptAlgorithm("3DES");

//  Tell the email to use this CSP:
email.SetCSP(csp);

success = mailman.SendEmail(email);
if (success != true) {
    MessageBox.Show(mailman.LastErrorText);
}
else {
    //  Examine the LastErrorText anyway, so we can see
    //  that 3DES was used...
    //  You should see these lines in the log:
    //  alg_name: 3DES
    //  alg_bits: 168
    MessageBox.Show(mailman.LastErrorText);
}