I've been called to one of secretary PCs running Windows 7 with complain that pictures are no longer visible with Thumbnail preview.
The problem is pretty trivial but with today''s Viruses boom, my first logical reaction was it is caused by some Virus or Spyware. After scanning thoroughfully the PC and finding nothing suspicious in msconfig I remembered to check in Windows Explorer Folder Options and this was it. Problem can be fixed by tuning Windows Explorer Folder Options settings. By default Folder Options menu is not visible in Windows 7 so to display menu first had to press Alt+F.
After pressing Alt+F navigate to:
Tools -> Folder Options -> View (tab) -> Untick (Always show icons, never thumbnails)
That's all Apply new settings and its resolved, pictures will be visible in Explorer and Desktop again 🙂