(Visual Basic 6.0) Add S/MIME Signature using PFX

Add a digital signature to a MIME message using the certificate + private key from a PFX file.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

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

Dim mime As New ChilkatMime

' Load a PFX file into a certificate object.
Dim cert As New ChilkatCert
Dim pfxFilepath As String
pfxFilepath = "pfxFiles/something.pfx"
Dim pfxPassword As String
pfxPassword = "secret"
Dim success As Long
success = cert.LoadPfxFile(pfxFilepath,pfxPassword)
If (success = 0) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

success = mime.SetBodyFromPlainText("This is the plain-text MIME body.")

mime.Charset = "utf-8"
mime.Encoding = "quoted-printable"

' Sign the MIME (adds a PKCS7 detached signature)
success = mime.AddDetachedSignature(cert)
If (success = 0) Then
    Debug.Print mime.LastErrorText
    Exit Sub
End If

' Save the S/MIME to a file.
success = mime.SaveMime("/temp/signedMime.txt")
If (success = 0) Then
    Debug.Print mime.LastErrorText
    Exit Sub
End If

Debug.Print "success!"