If you can't remove it via the usual way, it means the installer is broken or you're missing the files. You can re-install the application and then remove it or you can try using Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all the traces of its presence from the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.
