Internet Explorer 9 about:Tabs page lists the most visited sites (or this is what it's supposed to do); however, it doesn't work as expected.

I came to several occasions where: 1. the list doesn't display the sites that I visit often, 2. a recently visited page show up in the list 3. the list got reset or many sites removed from it if Internet Explorer was forcibly closed 4. and so on

where does it store the information about the sites? And is it possible to hack the list and force to display the sites that you want/expect?