VB.NET

Check if a Received Email Was Decrypted

Demonstrates the read-only Chilkat Email.Decrypted property, which is true if the email arrived encrypted and was successfully decrypted. This property is only meaningful when ReceivedEncrypted is true, so you should always check ReceivedEncrypted first — a false value can mean either that the message was not encrypted or that decryption did not succeed. This example loads a received email and reports its encryption/decryption status.

Background: Encrypted email typically uses S/MIME. The sender encrypts the message with the recipient's public-key certificate, and only the holder of the matching private key can decrypt it. When Chilkat loads such a message and has access to the private key, it decrypts automatically; ReceivedEncrypted tells you the message arrived encrypted, and Decrypted tells you whether decryption succeeded.

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VB.NET

Dim success As Boolean = False

'  Demonstrates the Email.Decrypted property.
'  Decrypted is true if the email arrived encrypted and was successfully
'  decrypted.  It is only meaningful when ReceivedEncrypted is true.

Dim email As New Chilkat.Email

'  Load an email that was received (from a .eml file).
success = email.LoadEml("qa_data/eml/received.eml")
If (success = False) Then
    Debug.WriteLine(email.LastErrorText)
    Exit Sub
End If


'  Always check ReceivedEncrypted first.
If (email.ReceivedEncrypted = True) Then
    If (email.Decrypted = True) Then
        Debug.WriteLine("The email was encrypted and was successfully decrypted.")
    Else
        Debug.WriteLine("The email was encrypted but could NOT be decrypted.")
    End If

Else
    Debug.WriteLine("The email did not arrive encrypted.")
End If