Please help I'm not sure what has happened but most of my photos have disappeared from Light Room on my computer. My latest collection is showing but not my previous photos. I have looked in the FAQ and I can find a few of my collections but not everything. I then tried to sync some new photos with my mobile phone and now my old photos are missing from there too. I don't really understand where everything has gone. Any help or advise would be gratefully received.
Sounds like you accidentally opened the wrong catalog file. Go to File->Open Recent and select each item in the list until you find the catalog of interest.