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Send Encrypted Email with a Selected Algorithm (AES, 3DES, etc.)

Sends an encrypted email using the recipient's digital certificate from a .cer file, and chooses 3DES for the encryption algorithm. (It is also possible to send AES encrypted email w/ 128-bit, 192-bit, or 256-bit encryption simply by setting the Pkcs7CryptAlg and Pkcs7KeyLength properties.)

Chilkat AutoIt Downloads

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Local $bSuccess = False

; This example requires the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.

; The mailman object is used for sending and receiving email.
$oMailman = ObjCreate("Chilkat.MailMan")

; Set the SMTP server.
$oMailman.SmtpHost = "smtp.mymailserver.com"

; Load the .cer file into a certificate object.
; When sending S/MIME encrypted email, it is the recipient's
; certificate that is used for encryption.  Only the public key
; is needed to encrypt.  The recipient is the only
; one possessing the private key, and therefore is the only
; one able to decrypt.
$oCert = ObjCreate("Chilkat.Cert")
$bSuccess = $oCert.LoadFromFile("cknotes.cer")
If ($bSuccess <> True) Then
    ConsoleWrite($oCert.LastErrorText & @CRLF)
    Exit
EndIf

; Create a new email object
$oEmail = ObjCreate("Chilkat.Email")

$oEmail.Subject = "This email is encrypted"
$oEmail.Body = "This is a digitally encrypted mail"
$oEmail.From = "Chilkat Support <support@chilkatsoft.com>"
$bSuccess = $oEmail.AddTo("Chilkat Blog","admin@cknotes.com")

; Indicate that the email is to be sent encrypted.
$oEmail.SendEncrypted = True

; Specify the certificate to be used for encryption.
$bSuccess = $oEmail.SetEncryptCert($oCert)

; If desired, specify the encryption algorithm to be used.
; The Pkcs7CryptAlg property can be set to "aes", "des", "3des", or "rc2"
$oEmail.Pkcs7CryptAlg = "3des"

; If desired, set the key length (in bits) for the encryption algorithm:
; The possible values allowed depend on the Pkcs7CryptAlg property. 
; For "aes", the key length may be 128, 192, or 256. 
; For "3des" the key length must be 192. 
; For "des" the key length must be 40. 
; For "rc2" the key length can be 40, 56, 64, or 128.
$oEmail.Pkcs7KeyLength = 192

$bSuccess = $oMailman.SendEmail($oEmail)
If ($bSuccess <> True) Then
    ConsoleWrite($oMailman.LastErrorText & @CRLF)
Else
    ConsoleWrite("Mail Sent!" & @CRLF)
EndIf