From time to time, you get an faulty program uninstallation that leaves certain left-over files that are later impossible to delete because according to your system, they are still in use and cannot be removed. To wipe these files once and for all, use Pocket KillBox. With this program, you can select the file that you would like to delete and once the computer is restarted, it will delete the file before it can be classed as "in use".