Encrypt MIME for Multiple Recipients

See more MIME Examples

Demonstrates encrypting the current MIME entity for several recipients at once. A certificate is added for each recipient with AddEncryptCert, and EncryptN then produces a single CMS/PKCS #7 message that each recipient can independently decrypt.

The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Dim success As Boolean = False

Dim mime As New Chilkat.Mime
success = mime.SetBodyFromPlainText("This message will be encrypted.")
If (success = False) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


'  Add a certificate for each intended recipient.  Every recipient receives an independently
'  wrapped copy of the message key.
Dim cert1 As New Chilkat.Cert
success = cert1.LoadFromFile("qa_data/recipient1.cer")
If (success = False) Then
    Debug.WriteLine(cert1.LastErrorText)
    Exit Sub
End If

success = mime.AddEncryptCert(cert1)
If (success = False) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


Dim cert2 As New Chilkat.Cert
success = cert2.LoadFromFile("qa_data/recipient2.cer")
If (success = False) Then
    Debug.WriteLine(cert2.LastErrorText)
    Exit Sub
End If

success = mime.AddEncryptCert(cert2)
If (success = False) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


'  Encrypt for every added recipient at once.
success = mime.EncryptN()
If (success = False) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


success = mime.SaveMime("qa_output/encrypted_multi.eml")
If (success = False) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("Message encrypted for multiple recipients.")