Need to decrypt the file in windows 8 (VS 2012) and WP8.1(VS 2013).

Question

I am decrypting a file which is already encrypted and working fine android app
I tried this code in Windows 8 using Visual Studio 2012.
  public string pw = "3x5FBNs!";
public string AES_Decrypt(string input, string pass)
      SymmetricKeyAlgorithmProvider SAP = SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithmNames.AesEcbPkcs7);
      CryptographicKey AES;
      HashAlgorithmProvider HAP = HashAlgorithmProvider.OpenAlgorithm(HashAlgorithmNames.Md5);
      CryptographicHash Hash_AES = HAP.CreateHash();
      string decrypted = "";
      try
        byte[] hash = new byte[32];
        Hash_AES.Append(CryptographicBuffer.CreateFromByteArray(System.Text.Encoding.UTF8.GetBytes(pass)));
        byte[] temp;
        CryptographicBuffer.CopyToByteArray(Hash_AES.GetValueAndReset(), out temp);
        Array.Copy(temp, 0, hash, 0, 16);
        Array.Copy(temp, 0, hash, 15, 16);
        AES = SAP.CreateSymmetricKey(CryptographicBuffer.CreateFromByteArray(hash));
        IBuffer Buffer = CryptographicBuffer.DecodeFromBase64String(input);
        byte[] Decrypted;
        CryptographicBuffer.CopyToByteArray(CryptographicEngine.Decrypt(AES, Buffer, null), out Decrypted);
        decrypted = System.Text.Encoding.UTF8.GetString(Decrypted, 0, Decrypted.Length);
        return decrypted;
      catch (Exception ex)
        return null;
Its always through an error "Bad Data. (Exception from HRESULT: 0x80090005)"
Here is the Android code which is using for decrypt the same file
package com.enable;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.security.Key;
import java.security.spec.KeySpec;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.net.util.Base64;
import com.enable.classes.Singleton;
import com.enable.classes.XMLPullParserHandler;
import com.enable.classes.XMLPullParserStringHandler;
import android.annotation.SuppressLint;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.AssetManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.preference.PreferenceManager;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.CheckBox;
import android.widget.FrameLayout;
public class MainActivity extends DrawerActivity{//{//ActionBarActivity{//DrawerActivity{//{
public final static String SETTINGS_FILE = "settings_e3.xml";
public final static String SETTINGS_FILE_E = "settings.xml";
private ProgressDialog progressDialog = null;
CheckBox tncCheckBox;
@SuppressLint("InflateParams")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
FrameLayout frameLayout = (FrameLayout)findViewById(R.id.content_frame);
   // inflate the custom activity layout
   LayoutInflater layoutInflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
   View activityView = layoutInflater.inflate(R.layout.activity_main, null,false);
   // add the custom layout of this activity to frame layout.
   frameLayout.addView(activityView);
   // now you can do all your other stuffs
   tncCheckBox = (CheckBox) findViewById(R.id.tncCheckBox);
   //continue if the file is available and the terms and conditions are checked
   SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(MainActivity.this);
   boolean checkedStatus = preferences.getBoolean("TnCAgreed", false);
   if(checkedStatus)
new ParseAndLoadTask().execute();
   //load default settings
   boolean useDefaultSetting = preferences.getBoolean("useDefaultSettings", true);
   if(useDefaultSetting)
   SharedPreferences.Editor editor = preferences.edit();
editor.putString("serverName", "Default 2Enable Server");
       editor.putString("hostIP", "192.168.1.199");
       editor.putInt("port", 21);
       editor.putString("username", "2Enable");
       editor.putString("password", "2En@ble2");
       editor.putBoolean("ftpCheck", false);
       editor.putBoolean("internetCheck", true);
       editor.commit();
public void GetFTPDetails()
Intent intent = new Intent(MainActivity.this, GetFTPDetailsActivity.class);
    startActivity(intent);
    finish();
public void LoadTnC(View view) throws IOException {
Intent intent = new Intent(MainActivity.this, TnCActivity.class);
        startActivity(intent);
        finish();
public void LoadEssencePage(View view) throws IOException {
Intent intent = new Intent(MainActivity.this, EssenceActivity.class);
         startActivity(intent);
         finish();
/** Called when the user clicks the button 
* @throws IOException */
    public void ProceedToLearningArea(View view) throws IOException {
        // Start a new thread that will download all the data
    if(tncCheckBox.isChecked())
    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
    SharedPreferences.Editor editor = preferences.edit();
    editor.putBoolean("TnCAgreed", true);
    editor.commit();
    new ParseAndLoadTask().execute();
    else
    AlertDialog.Builder alertDialog = new AlertDialog.Builder(
            MainActivity.this);
            // Setting Dialog Message
            alertDialog.setTitle("Cannot Proceed");
            alertDialog.setMessage("Kindly read and accept the Terms and Conditions to Proceed.");
            alertDialog.setCancelable(false);
            // Setting Icon to Dialog
            // Setting OK Button
            alertDialog.setPositiveButton("OK",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog,
                                int id) {
                            dialog.cancel();
            alertDialog.show();
    private String convertStreamToString(InputStream is) {
   BufferedReader reader = new BufferedReader(new InputStreamReader(is));
   StringBuilder sb = new StringBuilder();
   String line = null;
   try {
       while ((line = reader.readLine()) != null) {
           sb.append(line + "\n");
   } catch (IOException e) {
       e.printStackTrace();
   } finally {
       try {
           is.close();
       } catch (IOException e) {
           e.printStackTrace();
   return sb.toString();
    private static Cipher getCipher(int mode) throws Exception {
       Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
       //a random Init. Vector. just for testing
       byte[] iv = "e675f725e675f725".getBytes("UTF-8");
       c.init(mode, generateKey(), new IvParameterSpec(iv));
       return c;
   private static String Decrypt(String encrypted) throws Exception {
       byte[] decodedValue = new Base64().decode(encrypted.getBytes("UTF-8")); // new BASE64Decoder().decodeBuffer(encrypted);
       Cipher c = getCipher(Cipher.DECRYPT_MODE);
       byte[] decValue = c.doFinal(decodedValue);
       return new String(decValue);
   private static Key generateKey() throws Exception {
       SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
       char[] password = "3x5FBNs!".toCharArray();
       byte[] salt = "S@1tS@1t".getBytes("UTF-8");
       KeySpec spec = new PBEKeySpec(password, salt, 65536, 128);
       SecretKey tmp = factory.generateSecret(spec);
       byte[] encoded = tmp.getEncoded();
       return new SecretKeySpec(encoded, "AES");
    private class ParseAndLoadTask extends AsyncTask<String, Void, Void> 
    protected void onPreExecute (){
       MainActivity.this.progressDialog = ProgressDialog.show(MainActivity.this, "Please Wait.", "Loading Data...", true, false);
        protected Void doInBackground(String... args) {
    try {
    //check if the settings.xml file is available
           File extStore = Environment.getExternalStorageDirectory();
File myFile = new File(extStore.getAbsolutePath() + "/2Enable/"+SETTINGS_FILE_E);
if(myFile.exists() && myFile.length()>0)
FileInputStream fileInputStream = new FileInputStream(myFile);
XMLPullParserStringHandler parser = new XMLPullParserStringHandler();
String  data = convertStreamToString(fileInputStream);
    try 
String decrypt = Decrypt(data);
Singleton.setSettings(parser.parse(decrypt));
    catch (Exception e) 
e.printStackTrace();
else
AssetManager assetManager = getBaseContext().getAssets();
               InputStream fileInputStream = null;
               fileInputStream = assetManager.open(SETTINGS_FILE_E);
if(fileInputStream != null)
XMLPullParserStringHandler parser = new XMLPullParserStringHandler();
String Data = convertStreamToString(fileInputStream);
String decrypt = null;
try 
decrypt = Decrypt(Data);
Singleton.setSettings(parser.parse(decrypt));
catch (Exception e) 
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
return null;
            //return "replace this with your data object";
        protected void onPostExecute(Void result) {
            if (MainActivity.this.progressDialog != null) 
                MainActivity.this.progressDialog.dismiss();
            Intent intent = new Intent(MainActivity.this, LearningAreaActivity.class);
            startActivity(intent);
            finish();
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
return super.onOptionsItemSelected(item);
sandeep chauhan

Answer 1

Hi
Please provide your issue so that we can understand where you are facing issue.
For AES encryption please refer the msdn link
https://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged(v=vs.110).aspx
Regards
Varun Ravindranath Please 'Mark as Answer' if my post answers your question and 'Vote as Helpful' if it helps you.