Page password protection not working

I have a page that contains output from the wp-simplemeetingconfirmation plugin; it displays the names of people registering for a meeting.

In the UK this is classified as ‘personal data’ and is covered by our Data Protection Act, so it is imperative it is not accessible.

However, neither the ‘Private’ nor “the Password Protected’ options of the Visibility settings appear to work. (I have tried – obviously having first logged out of Dashboard and cleared the Borowser’s cache, as an additional precaution) but the page is still visible and the user is not redirected to the WP login page.

What’s more it appears in the Featured Content slider of the Suffusion theme, on the front page.

Can anyone suggest the reasons for this and what I could do about it?

I even tried with this plugin enabled, but it made no difference, so I deactivated it:
PC Hide Pages
Enables you to hide pages from WordPress menus, blog searches and search engines.
Version 1.0 | By Peter Coughlin |

Is anyone aware of any known plugin conflicts with the WP page visibility function? (sorry, I am afraid it is a rather extensive list).

Many thanks in advance for all and any help you might offer.

Best regards.

Gea

Installation set-up.
(just in case it helps)
Server Architecture: i686
OS: Linux, Litespeed
Apache version 2.2.21
PHP version 5.2.17
MySQL version 5.0.91-community-cll
Perl version 5.8.8
Kernel version 2.6.18-374.3.1.el5.lve0.8.44ent
WP version: 3.2.1, single site

PLUGINS:

1 Flash Gallery
Photo Gallery with slideshow function,
Version 1.7.5 | By 1plugin.com |

Akismet
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Version 2.5.3 | By Automattic |

BP Group Documents
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BuddyPress
Social networking in a box. Build a social network for your company, school, sports team or niche community all based on the power and flexibility of WordPress.
Version 1.5.1 | By The BuddyPress Community |

BuddyPress Group Email Subscription
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Version 2.9.5 | By Deryk Wenaus, boonebgorges |

BuddyPress Links
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BuddyPress Topic Mover
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Version 2.5.1 | By Deryk Wenaus |

Calendar
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Version 1.3.1 | By Kieran O’Shea |

Connections
A business directory and address book manager.
Version 0.7.1.6 | By Steven A. Zahm

Connections CSV
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Version 0.4 | By Steven A. Zahm |

Connections ROT13
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Version 0.1 | By Steven A. Zahm |

DH Admin Themes
The DH Admin Themes, WP3.x.x add a theme for the dashboard. You can customize the theme based on the provided sample.
Version 0.5.4 | By DREAMHIVE / mkoba |

Events
Enables you to show a list of events with a static countdown to date. Sidebar widget and page template options. And more…
Version 2.2.3 | By Arnan de Gans |

Greg’s High Performance SEO
Configure over 100 separate on-page SEO characteristics. Fewer than 700 lines of code per page view. No junk: just high performance SEO at its best.
Version 1.4.9.5 | By Greg Mulhauser |

Iframe Embedder
Lets you embed an iframe in a post
Version 1.2 | By de77.com |

Jet Event System for BuddyPress
The modern System of events for your social network. Ability to attract members of the network to the ongoing activities, a wide range of possibilities and options, support for different types of display, etc. JES DEV Site. Before you install or upgrade sure to read the Readme file!
Version 1.7.0.1 | By Jettochkin |

jQuery Slick Menu
Creates a widget, which adds a sticky sliding menu from any WordPress custom menu.
Version 1.3.2 | By Lee Chestnutt |

Mass Messaging in Buddypress
With mass-messaging you can message; lots of people, members of a group or even members of an EventPress event.
Version 1.0.3 | By Eliott Robson |

oEmbed for BuddyPress
The easiest way to share your favorite content from sites like YouTube, Flickr, Hulu and more on your BuddyPress network.
Version 0.52 | By r-a-y |

Private BuddyPress
Protect your BuddyPress Installation from strangers. Only registered users will be allowed to view the installation.
Version 1.0.4 | By Dennis Morhardt |

Slick Contact Forms
Create quick and easy floating or slide out contact forms with animated validation error messages.
Version 1.3.3 | By Lee Chestnutt |

Suffusion BuddyPress Pack
This plugin is an add-on to the Suffusion WordPress Theme. It is based on the BuddyPress Template Pack, with the markup elements and enhancements specific to Suffusion.
Version 1.05 | By Sayontan Sinha |

TinyMCE Advanced
Enables advanced features and plugins in TinyMCE, the visual editor in WordPress.
Version 3.4.2.1 | By Andrew Ozz |

U BuddyPress Forum Attachment
Allows members to upload files on BuddyPress forum. Uploader is Ajax-based.
Version 1.2.1 | By Taehan Lee |

U BuddyPress Forum Editor
TinyMCE WYSIWYG HTML editor for BuddyPress Forum.
Version 1.3 | By Taehan Lee |

Widget Entries
Creates the Widget post-type in the administration area to make easier the edition of the text widgets, and also register a new widget to import the widget entries easily.
Version 0.1 | By Javier Márquez |

WordPress Importer
Import posts, pages, comments, custom fields, categories, tags and more from a WordPress export file.
Version 0.5 | By wordpressdotorg |

wp-simplemeetingconfirmation
Allows registered and/or non registered users to confirm if they will be present at a planned meeting and optionally add comments, number of participants coming with them, expiration date…
Version 1.8.3 | By Frederic VUONG |

WP Issuu
Embed Issuu publications inside a post
Version 2.15 | By Issuu