Add S/MIME Signature using PFX

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

Download Chilkat .NET for 4.0 Framework

Download Chilkat .NET for 64-bit 4.0 Framework (x64)

Download Chilkat .NET for 2.0 / 3.5 Framework

Download Chilkat .NET for 64-bit 2.0 / 3.5 Framework (x64)

Download Chilkat .NET for 1.0 / 1.1 Framework

Dim mime As New Chilkat.Mime()

Dim success As Boolean
success = mime.UnlockComponent("Anything for 30-day trial")
If (success = false) Then
    TextBox1.Text = TextBox1.Text & mime.LastErrorText & vbCrLf
    Exit Sub
End If


'  Load a PFX file into a certificate object.
Dim cert As New Chilkat.Cert()
Dim pfxFilepath As String
pfxFilepath = "pfxFiles/something.pfx"
Dim pfxPassword As String
pfxPassword = "secret"
success = cert.LoadPfxFile(pfxFilepath,pfxPassword)
If (success = false) Then
    TextBox1.Text = TextBox1.Text & cert.LastErrorText & vbCrLf
    Exit Sub
End If


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

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


'  Sign the MIME:
success = mime.AddDetachedSignature(cert)
If (success = false) Then
    TextBox1.Text = TextBox1.Text & mime.LastErrorText & vbCrLf
    Exit Sub
End If


'  Save the S/MIME to a file.
success = mime.SaveMime("c:/temp/signedMime.txt")
If (success = false) Then
    TextBox1.Text = TextBox1.Text & mime.LastErrorText & vbCrLf
    Exit Sub
End If


MsgBox("success!")