I've had lightroom for the past year but for a couple of months now lightroom just won't open. I click on the application and it comes up with a box saying 'The Lightroom catalog named "Lightroom Catalog" cannot be opened because another application has it opened' and gives me the option to choose a different catalog, continue or exit, however if I try to choose a different catalog none of my catalogs are there. Does anyone have any advise as to how to fix it?? I've already tried uninstalling lightroom and going into taskmanager to try and close everything thats open and they didn't work.
With Lr closed go to the location where your catalog resides(By default it is Pictures/Lightroom)
Delete the .Lock file with the same name as your catalog.For instance in the Picture below it is Lightroomcatalog.lrcat.lock
Let us know if that helps.