---
UID: NF:certenroll.IX509EndorsementKey.Open
title: IX509EndorsementKey::Open (certenroll.h)
description: Opens the endorsement key. The endorsement key must be open before you can retrieve an information from the endorsement key, add or remove certificates, or export the endorsement key.
old-location: security\ix509endorsementkey_open.htm
tech.root: seccertenroll
ms.assetid: 06855fc0-0d87-4fe7-9525-55eb60bffcd1
ms.date: 12/05/2018
ms.keywords: IX509EndorsementKey interface [Security],Open method, IX509EndorsementKey.Open, IX509EndorsementKey::Open, Open, Open method [Security], Open method [Security],IX509EndorsementKey interface, certenroll/IX509EndorsementKey::Open, security.ix509endorsementkey_open
f1_keywords:
- certenroll/IX509EndorsementKey.Open
dev_langs:
- c++
req.header: certenroll.h
req.include-header: 
req.target-type: Windows
req.target-min-winverclnt: 
req.target-min-winversvr: 
req.kmdf-ver: 
req.umdf-ver: 
req.ddi-compliance: 
req.unicode-ansi: 
req.idl: Certenroll.idl
req.max-support: 
req.namespace: 
req.assembly: 
req.type-library: 
req.lib: 
req.dll: Certenroll.dll
req.irql: 
topic_type:
- APIRef
- kbSyntax
api_type:
- COM
api_location:
- Certenroll.dll
api_name:
- IX509EndorsementKey.Open
targetos: Windows
req.typenames: 
req.redist: 
ms.custom: 19H1
---

# IX509EndorsementKey::Open


## -description


Opens the endorsement key. The endorsement key must be open before you can retrieve an information from the endorsement key, add or remove certificates, or export the endorsement key.


## -parameters






## -returns



If this method succeeds, it returns <b xmlns:loc="http://microsoft.com/wdcml/l10n">S_OK</b>. Otherwise, it returns an <b xmlns:loc="http://microsoft.com/wdcml/l10n">HRESULT</b> error code.




## -see-also




<a href="https://docs.microsoft.com/windows/desktop/api/certenroll/nn-certenroll-ix509endorsementkey">IX509EndorsementKey</a>
 

 

