I can't uninstall Rated 1 out of 5 stars

I didn't want this I have not installed this I tried to uninstall and now the button is greyed out and is still install I tried following instructions on link someone left in the reviews but the is no microsoftdotnet in my about:config.

What do I do uninstall Firefox?

This review is for a previous version of the add-on (1.2.1).