(PowerShell) S/MIME Encrypt .eml without Sending

See more Email Object Examples

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

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

$email = New-Object Chilkat.Email

$success = $email.LoadEml("c:/temp/email/unencrypted.eml")
if ($success -eq $false) {
    $($email.LastErrorText)
    exit
}

# The email content is encrypted using AES with a 256-bit key, operating in GCM mode, which provides authenticated encryption.
$email.Pkcs7CryptAlg = "aes-gcm"
$email.Pkcs7KeyLength = 256
$email.OaepPadding = $true
$email.OaepHash = "sha256"
$email.OaepMgfHash = "sha256"

$cert = New-Object Chilkat.Cert
$success = $cert.LoadFromFile("c/temps/cert/recipient.cer")
if ($success -eq $false) {
    $($cert.LastErrorText)
    exit
}

$email.SendEncrypted = $true
$email.SetEncryptCert($cert)

$sbSmime = New-Object Chilkat.StringBuilder

# The mailman object applies the encryption by rendering the email according to the instructions (property settings) provided in the email object.
# No email is sent.
$mailman = New-Object Chilkat.MailMan
$success = $mailman.RenderToMimeSb($email,$sbSmime)
if ($success -eq $false) {
    $($mailman.LastErrorText)
    exit
}

$success = $sbSmime.WriteFile("c:/temp/encryptedEmail.eml","utf-8",$false)
if ($success -eq $false) {
    $($mailman.LastErrorText)
    exit
}

$("Success!")