LR 5 stopped f unctioning. I get an error message that reads: "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." I have tried 5 or 6 times to reboot the computer and each time the same result with the same message. Hope you can help. Also, if I re-install LIGHTROOM will I lose all of my 3566 images?
In Explorer/Finder, in the same folder as your catalogue (usually in Pictures/Lightroom) is a file called Lightroom Catalog Previews.lrdata. Delete this file, and only this file, and you should be good to go.