I managed to break Kontact Personal Information Manager after Kontact>Settings>Configure Kontact and unticked all components listed, Apply. This caused Kontact to crash whenever I opened Kontact and clicked on Settings>Configure Kontact. Terminal output says: 'the library "/usr/lib/kde4/kcm_(module name).so" does not offer a qt_plugin_instance function.'
To restore to a working Kontact, in file manager go to Home, show hidden files, navigate to .kde/share/config/kontactrc, right click on kontactrc and 'move to trash'. You can now start Kontact Personal Information Manager and click on Settings>Configure Kontact with no problems.