private static byte[] DecryptEnvelopeKeyUsingSymmetricKey(SymmetricAlgorithm symmetricAlgorithm, byte[] encryptedEnvelopeKey)
{
symmetricAlgorithm.Mode = CipherMode.ECB;
using (ICryptoTransform decryptor = symmetricAlgorithm.CreateDecryptor())
{
return (decryptor.TransformFinalBlock(encryptedEnvelopeKey, 0, encryptedEnvelopeKey.Length));
}
}