Windows 7 explorer thumbnails stop loading

Question

So my thumbnails in explorer work fine when I restart my computer, however, eventually they stop loading. Even the preview pane will no longer update... for any type of file. And occasionally the Favorites, Libraries, etc in the navigation pane will have a "searching" magnifying glass (forever).

I am not sure why this happens.

Answer 1

Turns out, there was a corrupt video file that when windows tried to make a thumbnail it would fail and stop making thumbnails altogether.