How do I password protect a single page?

I've installed the Protected Content plug-in and gone through the setup process (stating the page/category to be protected and membership name etc)... but the page I 'locked' just comes up with a 'Protected Content' title and no way of entering a password to access it. In fact I can't find any way of setting a password for members.

The padlock icon is not appearing on the visual editor of the WP interface either.

I just want to restrict access to a single page on our site with a password log-in. Will your Protected Content plug-in do this?

Many thanks, Andy