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Lua

Sending S/MIME Encrypted Email

Sends an encrypted email using the recipient's digital certificate from a .cer file.

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Lua
local chilkat = require("chilkat")

-- 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.
local mailman = chilkat.MailMan.new()

-- Set the SMTP server.
mailman.smtp_host = "smtp.comcast.net"

-- 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.
local cert = chilkat.Cert.new()
local success = cert:load_from_file("cknotes.cer")
if not success then
    print(cert.last_error_text)
    return
end

-- Create a new email object
local email = chilkat.Email.new()

email.subject = "This email is encrypted"
email.body = "This is a digitally encrypted mail"
email.from = "Chilkat Support <support@chilkatsoft.com>"
success = email:add_to("Chilkat Blog", "admin@cknotes.com")

-- Indicate that the email is to be sent encrypted.
email.send_encrypted = true

-- Specify the certificate to be used for encryption.
success = email:set_encrypt_cert(cert)

success = mailman:send_email(email)
if not success then
    print(mailman.last_error_text)
else
    print("Mail Sent!")
end