javax.crypto.BadPaddingException: Given final block not properly padded

[Muneeb Kiani]

hi..!

i'm having this exception, when i tried to decrypt a msg coming frm server... "javax.crypto.BadPaddingException: Given final block not properly padded". here is my code.

Encryption code

 byte[] encryption(int key, byte[] msg){

            long power = key;
            for(int i=0; i<=19; i++){
                power = power*key;
                System.out.println(power);
            }
            String str = Long.toString(power);
            System.out.println(str);

            String secrett = str.substring(0, 16);

            System.out.println("String key"+secrett);
            byte[] AESKey = secrett.getBytes();
            SecretKeySpec sk = new SecretKeySpec(AESKey, "AES");


        try {
                Cipher c = Cipher.getInstance("AES");

                c.init(Cipher.ENCRYPT_MODE, sk);

                cipher = c.doFinal(msg);
                } catch (Exception ex) {
                    Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
                }
            return cipher;

        }

Decryption Code:

 byte[] decryption(int key, byte[] msg){

           long power = key;
           for(int i=0; i<=35; i++){
            power = power*key;
            System.out.println(power);
           }

           String str = Long.toString(power);
           System.out.println("KKKKeeYYYY"+power);
            byte[] cipher = new byte[msg.length];
           /* for (int a = 0; a < 12589; a++) {
                power = power * keyy;
            }*/

            String secret = str.substring(0, 16);
            System.out.println("String key" + secret);
            byte[] AESKey = secret.getBytes();
            SecretKeySpec sk = new SecretKeySpec(AESKey, "AES");
            try{
            Cipher d = Cipher.getInstance("AES/ECB/PKCS5Padding");
            d.init(Cipher.DECRYPT_MODE, sk);
            cipher = d.doFinal(msg);
        } catch (Exception ex) {
            Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
        }

        return cipher;
        }

[greg stark]

You should read your own code. Your are clearly processing the key differently for encryption and decryption. Also, you are using defaults in the getInstance() method in the encryption code but you are fully specifying the mode and padding in that same method in the decryption code? How do you know they'll be the same?