Try using Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all traces of its presence from the system.
Reboot the PC, then run Revo Uninstaller and look for the software. If it's there, repeat the uninstallation process and it should be gone forever.
If Revo Uninstaller is too complicated for you, use Geek Uninstaller: http://www.geekuninstaller.com/download
Note: The free version should be enough to remove the application.