C# DPAPI Example Usage

encrypt.cs

using System;
using System.Security.Cryptography;
using System.Text;

namespace Encrypt1
{
    internal class Program
    {

        readonly static byte[] entropy = {}; //the entropy

        private static string Encrypt(string text)
        {
            // first, convert the text to byte array 
            byte[] originalText = Encoding.Unicode.GetBytes(text);

            // then use Protect() to encrypt your data 
            byte[] encryptedText = ProtectedData.Protect(originalText, entropy, DataProtectionScope.CurrentUser);

            //and return the encrypted message 
            return Convert.ToBase64String(encryptedText);
        }

        private static string Decrypt(string text)
        {
            // the encrypted text, converted to byte array 
            byte[] encryptedText = Convert.FromBase64String(text);

            // calling Unprotect() that returns the original text 
            byte[] originalText = ProtectedData.Unprotect(encryptedText, entropy, DataProtectionScope.CurrentUser);

            // finally, returning the result 
            return Encoding.Unicode.GetString(originalText);
        }

        static void Main(string[] args)
        {
            String toEncrypt = "SuperSoooooSecret";
            Console.WriteLine("Value to encrypt: {0}", toEncrypt);
            String encrypted = Encrypt(toEncrypt);
            Console.WriteLine("Encrypted: {0}", encrypted);
            Console.WriteLine("Decrypted: {0}", Decrypt(encrypted));
        }
    }
}