X509Certificate2: Internal error

When I try to execute code below I got an error:

Internal error occurred.

var certificate = new X509Certificate2( p12FileBytes, p12FilePassword );

when I added

X509KeyStorageFlags.MachineKeySet(
   new X509Certificate2(
      p12FileBytes, p12FilePassword,  X509KeyStorageFlags.MachineKeyS开发者_如何学运维et)).

I got another error:

Access Denied.

How can I fix it?

Thanks in advance.

Regards,

Stepan.

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Run the second code with elevated privileges.