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Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

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How to create a PKCS12 (.p12 or .pfx) from a certificate file and private key file: Demonstrates how to duplicate this OpenSSL command:
Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

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Local $bSuccess = False

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

$oPkey = ObjCreate("Chilkat.PrivateKey")

; Load the private key from the file.
$bSuccess = $oPkey.LoadAnyFormatFile("certFile.key","")
If ($bSuccess <> True) Then
    ConsoleWrite($oPkey.LastErrorText & @CRLF)
    Exit
EndIf

$oCert = ObjCreate("Chilkat.Cert")
; The LoadFromFile method auto-recognizes the format...
$bSuccess = $oCert.LoadFromFile("certfile.cer")
If ($bSuccess <> True) Then
    ConsoleWrite($oCert.LastErrorText & @CRLF)
    Exit
EndIf

; We'll need a cert chain object to create the PKCS12, so get it
; from the cert.  
Local $oCertChain
$oCertChain = $oCert.GetCertChain()
If (Not $oCert.LastMethodSuccess) Then
    ConsoleWrite($oCert.LastErrorText & @CRLF)
    Exit
EndIf

; Create the PFX object, add the cert and private key, and write to a .pfx file.
$oPfx = ObjCreate("Chilkat.Pfx")

; The cert(s) are automatically added in the call to AddPrivateKey
$bSuccess = $oPfx.AddPrivateKey($oPkey,$oCertChain)
If ($bSuccess <> True) Then
    ConsoleWrite($oPfx.LastErrorText & @CRLF)
    Exit
EndIf

; Write the .pfx to a file.
Local $sPassword = "myPassword"
$bSuccess = $oPfx.ToFile($sPassword,"certfile.pfx")
If ($bSuccess <> True) Then
    ConsoleWrite($oPfx.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Success." & @CRLF)