Subscribe2 Widget Pro enhances the capabilities of Subscribe2 via an advanced subscription widget with many additional options.
Maybe it's not working with the new wordpress?
The widget will NOT send in confirmation email for new subscribers despite making page and adding [subscribe] shortcode, and pointing the widget to that page. (Which is not fully disclosed either on installation page - it says to upload and that's it - obviously it isn't. You have to go to FAQ page which then tells you that you must make a page with short code - and some more search to figure out the short code)
All to discover that it doesn't work anyway.
Had to use the jetpack subscribe button instead.