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X509ClientCertificateAuthentication Class

Specifies authentication properties for validating the client certificate.

Namespace:  System.ServiceModel.Security
Assembly:  System.ServiceModel (in System.ServiceModel.dll)

public class X509ClientCertificateAuthentication

If the CertificateValidationMode is set to Custom, then you must create a custom certificate validator that inherits from the X509CertificateValidator class. For more information, see How To: Create a Service Employing a Custom Certificate Validator.

The following code shows how to set this property.

// Create a service host.
Uri httpUri = new Uri("http://localhost/Calculator");
ServiceHost sh = new ServiceHost(typeof(Calculator), httpUri);

// Get a reference to the authentication object.
X509ClientCertificateAuthentication myAuthProperties =

// Configure peer trust.
myAuthProperties.CertificateValidationMode =
// Configure chain trust.
myAuthProperties.CertificateValidationMode =
// Configure custom certificate validation.
myAuthProperties.CertificateValidationMode =

// Specify a custom certificate validator (not shown here) that inherits  
// from the X509CertificateValidator class.  
// creds.ClientCertificate.Authentication.CustomCertificateValidator = 
//    new MyCertificateValidator();

The property can also be set in a configuration file.

     <authentication certificateValidationMode='ChainTrust' />


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0

.NET Compact Framework

Supported in: 3.5