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. Revo will force the uninstall procedure. Alternatively, click the Advanced Uninstall, select the application in the list and that's it.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.