(VBScript) 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 ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Email")
set email = CreateObject("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.)
success = email.AddPfxSourceFile("/pfxFiles/certs_and_keys_1.pfx","pfxPassword1")
If (success <> 1) Then
    outFile.WriteLine(email.LastErrorText)
    WScript.Quit
End If

success = email.AddPfxSourceFile("/pfxFiles/certs_and_keys_2.pfx","pfxPassword2")
If (success <> 1) Then
    outFile.WriteLine(email.LastErrorText)
    WScript.Quit
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 = 1) Then

    outFile.WriteLine("This email was encrypted.")
    If (email.Decrypted = 1) Then
        outFile.WriteLine("This email was successfully decrypted.  It was encrypted by:")
        outFile.WriteLine(email.EncryptedBy)
    Else
        outFile.WriteLine("This email was not decrypted.")
    End If

End If

If (email.ReceivedSigned = 1) Then

    outFile.WriteLine("This email was signed.")
    If (email.SignaturesValid = 1) Then
        outFile.WriteLine("The signature was verified.  It was signed by:")
        outFile.WriteLine(email.SignedBy)
    Else
        outFile.WriteLine("The signature verification failed.")
    End If

End If

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

outFile.Close