(VB.NET) Load Signed and/or Encrypted Email and Unwrap Security Layers

The LoadEml method loads an email (.eml file containing the MIME of an email) and automatically unwraps the digital signature and encryption security layers. A program can then examine the properties of the email object to see what was unwrapped.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

Dim email As New Chilkat.Email

'  Provide PFX/.p12 files for any certs+keys needed for decryption.
'  Signature verification does not need anything extra.
'  (Also, Chilkat will automatically find and use pre-installed certs + private keys needed for decryption
'  on a Windows system.)
Dim success As Boolean = email.AddPfxSourceFile("/pfxFiles/certs_and_keys_1.pfx","pfxPassword1")
If (success <> True) Then
    Debug.WriteLine(email.LastErrorText)
    Exit Sub
End If

success = email.AddPfxSourceFile("/pfxFiles/certs_and_keys_2.pfx","pfxPassword2")
If (success <> True) Then
    Debug.WriteLine(email.LastErrorText)
    Exit Sub
End If

'  ...

'  Load a potentially signed and/or encrypted email.
success = email.LoadEml("someDir/someEmail.eml")

'  If the email was signed and/or encrypted, it was "unwrapped", i.e.
'  the email is already decrypted and in a state as if it were never signed or encrypted.

'  You may check to see if the email was received encrypted or signed, and if so,
'  whether it was successfully unwrapped and who signed or encrypted it:
If (email.ReceivedEncrypted = True) Then

    Debug.WriteLine("This email was encrypted.")
    If (email.Decrypted = True) Then
        Debug.WriteLine("This email was successfully decrypted.  It was encrypted by:")
        Debug.WriteLine(email.EncryptedBy)
    Else
        Debug.WriteLine("This email was not decrypted.")
    End If

End If

If (email.ReceivedSigned = True) Then

    Debug.WriteLine("This email was signed.")
    If (email.SignaturesValid = True) Then
        Debug.WriteLine("The signature was verified.  It was signed by:")
        Debug.WriteLine(email.SignedBy)
    Else
        Debug.WriteLine("The signature verification failed.")
    End If

End If


'  At this point, the contents of the email, including attachments, can be accessed normally..