X509Certificate.CreateFromCertFile Method (String)


Creates an X.509v3 certificate from the specified PKCS7 signed file.

Namespace:   System.Security.Cryptography.X509Certificates
Assembly:  mscorlib (in mscorlib.dll)

public static X509Certificate CreateFromCertFile(
	string filename


Type: System.String

The path of the PKCS7 signed file from which to create the X.509 certificate.

Return Value

Type: System.Security.Cryptography.X509Certificates.X509Certificate

The newly created X.509 certificate.

Exception Condition

The filename parameter is null.

ASN.1 DER is the only certificate format supported by this class.


The certificate file is not restricted to .cerfiles. Any PKCS7 signed file can be used, including an Authenticode signed .pfx file.

The following example creates an X509Certificate from a specified certification file.

using System;
using System.Security.Cryptography.X509Certificates;

public class X509

    public static void Main()

        // The path to the certificate.
        string Certificate =  "Certificate.cer";

        // Load the certificate into an X509Certificate object.
        X509Certificate cert = X509Certificate.CreateFromCertFile(Certificate);

        // Get the value.
        string resultsTrue = cert.ToString(true);

        // Display the value to the console.

        // Get the value.
        string resultsFalse = cert.ToString(false);

        // Display the value to the console.



.NET Framework
Available since 1.1
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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