(VB.NET) Decrypt a .p7m File (using a PFX)

VB.NET sample code showing how to decrypt a .p7m using a .p12 / .pfx certificate w/ private key.

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

Dim crypt As New Chilkat.Crypt2

' Use a digital certificate and private key from a PFX file (.pfx or .p12).
Dim pfxPath As String = "myCertAndKey.pfx"
Dim pfxPassword As String = "test123"

Dim success As Boolean = crypt.AddPfxSourceFile(pfxPath,pfxPassword)
If (success <> True) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


' Set the  outPath to whatever is appropriate.
' If you are decrypting a PDF, your output might be "out.pdf"...
Dim inPath As String = "smime.p7m"
Dim outPath As String = "original.txt"

' Indicate that we're doing public key decryption (i.e. PKCS7)
crypt.CryptAlgorithm = "pki"

success = crypt.CkDecryptFile(inPath,outPath)
If (success = False) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("Success.")