Hi Folks: This is a new one on me. Opened up Lightroom (2.6, under Windows 7), and instead of having thumbnail images in the Library Grid I only have little gray placeholders. Same in Develop, Slideshow, Print... no 'images'. Pick flags are shown, as are star ratings and colours Now the files themselves are all where they're supposed to be, and my LR3 catalog looks fine... See image for what I'm talking about. Any ideas?