How to export Certificate to PKCS# 7 format (.p7b file) RRS feed

  • Question

  • I am trying below code to export a certificate from machine store to PKCS# 7 format, but it fails with exception


    System.Security.Cryptography.CryptographicException was unhandled

      Message=Invalid content type.



           at System.Security.Cryptography.X509Certificates.X509Certificate.ExportHelper(X509ContentType contentType, Object password)

           at System.Security.Cryptography.X509Certificates.X509Certificate.Export(X509ContentType contentType)




    var chSignatureCert = machineStore.Certificates.Find(X509FindType.FindByThumbprint, "30 a7 1b 77 d7 71 a6 36 e7 c3 a3 e3 b7 80 a9 81 50 84 34 b0"false)[0];




    Can anyone provide any inputs on how to export cert in PKCS# 7 format?

    Monday, June 27, 2011 6:57 PM

All replies




    Welcome to the MSDN forum.


    Have you debug the code to see whether the chSigntureCert object in your code has got the Certificate? Does it contain a password in it?


    More information, please refer to:

    X509Certificate.Export Method

    Paul Zhou [MSFT]
    MSDN Community Support | Feedback to us
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    Please remember to mark the replies as answers if they help and unmark them if they provide no help.

    Tuesday, June 28, 2011 7:58 AM
  • sorry for late reply. I still don't have a solution for this.

    I can read other properties of certificate and it does not have any password.



    Saturday, August 6, 2011 10:58 AM
  • You can only export in pkcs7 format from the X5092Certificate Collection.

    var collection = new X509Certificate2Collection(chSignatureCert );

    var data = collection.Export(X509ContentType.Pkcs7);

    Tuesday, April 4, 2017 1:23 PM