using System;

using System.Security.Cryptography;

using System.IO;

using System.ComponentModel;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        string strText = "NjMDK5c7vIs=";

            if (strText == null || strText == "")

            {

                Console.WriteLine("Enter string is empty");

            }

            else

            {

                byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef };

                byte[] inputByteArray = new byte[strText.Length + 1];

                try

                {

                    string strEncrKey = "&%#@?,:*";

                    byte[] byKey = System.Text.Encoding.UTF8.GetBytes(strEncrKey.Substring(0, 8));

                    DESCryptoServiceProvider des = new DESCryptoServiceProvider();

                    inputByteArray = Convert.FromBase64String(strText);

                    MemoryStream ms = new MemoryStream();

                    CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);

                    cs.Write(inputByteArray, 0, inputByteArray.Length);

                    cs.FlushFinalBlock();

                    System.Text.Encoding encoding = System.Text.Encoding.UTF8;

                    Console.WriteLine(encoding.GetString(ms.ToArray()));

                }

                catch (Exception ex)

                {

                    Console.WriteLine("Error:" + ex.Message);

                }

            }

    }

}