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.
Dim mailman As New Chilkat.MailMan()

'  Any string argument automatically begins the 30-day trial.
Dim success As Boolean
success = mailman.UnlockComponent("30-day trial")
If (success <> true) Then
    MsgBox("Component unlock failed")
    Exit Sub
End If


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

'  Create a new email object
Dim email As 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:
Dim csp As 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) Then
    MsgBox(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
    MsgBox(mailman.LastErrorText)
End If