public String recover(String szUsername,String szEmail,String szQuestion,
                        String szAnswer)throws IOException
  {
    Scanner scan = new Scanner(file);
    String[] szDec = null;
    String szPasscode = null;
    while(scan.hasNextLine())
    {
      szDec = Xor.decrypt(scan.nextLine()).split(":");
      if(szDec[0].equalsIgnoreCase(szUsername)&&
         szDec[2].equalsIgnoreCase(szEmail)&&
         szDec[3].equalsIgnoreCase(szQuestion)&&
         szDec[4].equalsIgnoreCase(szAnswer)
        )
        szPasscode = szDec[1];
    }
    scan.close();
    return szPasscode;
  }