Class for encryption and decryption using System; using System.IO; using System.Security.Cryptography;// Encryption & Decryption using DES algorithm public class clsDecrypt { //Encrypt function public static string strEncrypt(string strData, string strKey1, string strKey2) { MemoryStream ms = new MemoryStream(); DESCryptoServiceProvider objKey = new DESCryptoServiceProvider(); objKey.Key = objLockKey(strKey1); objKey.IV = objLockKey(strKey2); CryptoStream encStream = new CryptoStream(ms, objKey.CreateEncryptor(), CryptoStreamMode.Write); StreamWriter sw = new StreamWriter(encStream); sw.WriteLine(strData); sw.Close(); encStream.Close(); byte[] bytData = ms.ToArray(); string strReturnData = ""; foreach (byte bytChar in bytData) { strReturnData += bytChar.ToString().PadLeft(3, Convert.ToChar("0")); } ms.Close(); return strReturnData; }//Decrypt function public static string strDecrypt(string strData, string strKey1, string strKey2) { DESCryptoServiceProvider objKey = new DESCryptoServiceProvider(); objKey.Key = objLockKey(strKey1); objKey.IV = objLockKey(strKey2); Int16 intLength = Convert.ToInt16((strData.Length / 3)); byte[] bytData = new byte[intLength]; for (Int16 intCount = 0; intCount < intLength; intCount++) { string strChar = strData.Substring((intCount * 3), 3); bytData[intCount] = Convert.ToByte(strChar); } MemoryStream ms = new MemoryStream(bytData); CryptoStream encStream = new CryptoStream(ms, objKey.CreateDecryptor(), CryptoStreamMode.Read); StreamReader sr = new StreamReader(encStream); string strReturnVal = sr.ReadLine(); sr.Close(); encStream.Close(); ms.Close(); return strReturnVal; } private static byte[] objLockKey(string strPassword) { const int intKeyLength = 8; strPassword = strPassword.PadRight(intKeyLength, Convert.ToChar(".")).Substring(0, intKeyLength); byte[] objKey = new byte[strPassword.Length]; for (int intCount = 0; intCount < strPassword.Length; intCount++) { objKey[intCount] = Convert.ToByte(Convert.ToChar(strPassword.Substring(intCount, 1))); } return objKey; } }Call the above function from any page as below //encryption string encpassword=clsDecrypt .strEncrypt(password,"choice1" ,"choice2");//decryption string password= clsDecrypt. string strDecrypt(encpassword,"choice1","choice2"); hopes this will help you... Regards maddy.....