jdaniel on "Twitter Widget Pro - Range Dashboard Widget removal Part 2"

I once installed Twitter Widget Pro that comes along with a Dashboard Widget by Range (http://http//ran.ge/)

I disabled and deleted the Twitter Plugin long time ago. But I still have that Range widget on my Dashboard. How can I remove it? (It is displayed to all new users by default, which I don't want. So I don't just want "not to display it on MY dashboard individually", but delete it once and for all.)

Can anybody help me? (I read http://wordpress.org/support/topic/twitter-widget-pro-range-dashboard-widget-removal-1?replies=2, but it doesn't help if it's already installed.)

Thanks,
Daniel