I am having an issue with Lightroom previews that has only gotten worse with each fix I've read about. I am on version 5. I noticed a few moths ago that 1:1 previews in the develop module were soft, but they were ok in the library, If I exported to photoshop or a plug in they were sharp. If I tried to make any adjustments, I could see them made in the filmstrip below, but not on the large preview itself. If I went back to the library I could see the changes, but not at al in develop.
Then I started to lose the previews, first the big version, then in the detail area, then in navigation. Only in Develop, not in the library. As was suggested in a couple of places online, I deleted the .lrdata file, and let Lightroom rebuild previews. I don't know if I missed a step or what, but it has only gotten worse. I can't see anything outside of the library. I tried uninstalling and reinstalling, which didn't help. I'm at a loss, and Lightroom is unusable.