Weird Mars language displayed in upon decryption

   public string EncryptPassWord(string password)
    {
        if (string.IsNullOrEmpty(password)) throw new ArgumentNullException("password");
        string en_password = null;

        RijndaelManaged aesPassword = null;

        try
        {
            Rfc2898DeriveBytes passwordkey = new Rfc2898DeriveBytes(password, _salt);

            aesPassword = new RijndaelManaged();
            aesPassword.Padding = PaddingMode.None;

            ICryptoTransform passwordEncryptor = aesPassword.CreateEncryptor(aesPassword.Key, aesPassword.IV);

            using (MemoryStream passEncryptor = new MemoryStream())
            {
                passEncryptor.Write(BitConverter.GetBytes(aesPassword.IV.Length), 0, sizeof(int));
                passEncryptor.Write(aesPassword.IV, 0, aesPassword.IV.Length);
                using (CryptoStream cspassEncrypt = new CryptoStream(passEncryptor, passwordEncryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swpassEncryptor = new StreamWriter(cspassEncrypt))
                    {
                        swpassEncryptor.Write(password);
                    }
                }
                en_password = Convert.ToBase64String(passEncryptor.ToArray());
            }

        }
        finally
        {
            if (aesPassword != null) { aesPassword.Clear(); }
        }
        return en_password;
    }







public string DecryptPassword(string dePassword)
    {
        if (string.IsNullOrEmpty(dePassword)) throw new ArgumentNullException("dePassword");

        RijndaelManaged aesDePassword = null;
        string deCPassword = null;

        try
        {
            Rfc2898DeriveBytes dePassKey = new Rfc2898DeriveBytes(dePassword, _salt);

            byte[] bytes = Convert.FromBase64String(dePassword);
            using(MemoryStream msPassDecrypt = new MemoryStream(bytes))
            {
                aesDePassword = new RijndaelManaged();
                aesDePassword.Padding = PaddingMode.None;
                aesDePassword.Key = dePassKey.GetBytes(aesDePassword.KeySize / 8);
                aesDePassword.IV = ReadByteArray(msPassDecrypt);

                ICryptoTransform passDecryptor = aesDePassword.CreateDecryptor(aesDePassword.Key, aesDePassword.IV);
                using (CryptoStream csPassDecrypt = new CryptoStream(msPassDecrypt, passDecryptor, CryptoStreamMode.Read))
                {
                    using(StreamReader srPassDecrypt = new StreamReader(csPassDecrypt))
                    {
                        deCPassword = srPassDecrypt.ReadToEnd();
                    }
                }

            }
        }
        finally
        {
            if (aesDePassword != null)
            {
                aesDePassword.Clear();
            }
        }

        return deCPassword;
    }









    private static byte[] ReadByteArray(Stream s)
    {
        byte[] rawLength = new byte[sizeof(int)];
        if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
        {
            throw new SystemException("Stream did not contain properly formatted byte array");
        }

        byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
        if(s.Read(buffer, 0, buffer.Length) != buffer.Length)
        {
            throw new SystemException("Did not read byte array properly");
        }
        return buffer;
    }