* @return an unique id identifying the computer based on it's hardware if a
* supported operating system (Windows, Linux, Mac OSX) is
* installed; null otherwise
*/
private static String getStrongComputerUUID() {
final OS currOs = SysUtil.getOS();
final String uuid;
switch (currOs) {
case WINDOWS:
uuid = getStrongComputerUUIDwindows();
break;