For the last month Lightroom has given me this message: "Lightroom encountered an error when reading from its preview cache and needs to quit. Lightroom will attempt to fix this problem the next time it launches." way to often. I have tried to delete the preview cache with no success, usually it will just give me the same message when trying to build new previews. I have also tried deleting the preference file without any success. Yesterday I could not take it any more and I deleted my catalog as well as reinstalled Lightroom. Not only did it fix my problem, but Lightroom is now way, way faster in navigating the library, importing and exporting. Does anybody know what the problem could have been? I would like to prevent this from happening again. And even though I deleted my catalog with all the adjustments, som pictures (RAW files) still have them. Very few, maybe 1 out of 1000, but what is the reason?