Is Lightroom Really Loosing Files?
I've been working with Lightroom since version 1 and to date it did not loose or screw up a single photo of mine. However, some times there are horror stories of users who open Lightroom and find out that all their photos are gone. I always had the suspicion that these stories are purely based on user errors. After reading the excellent article of Helen Bradley on DPS I am even more confident about it
If you think a folder should be displaying more images than it does, check that there is not a Custom Filter in place. In the Library module, make sure the Filmstrip is visible and if there is a filter listed in the Filter box then that’s affecting what you’re seeing. To return to showing all your images in the currently selected folder, select Filters Off from the Filters list.