I am running Lightroom stand alone without CC on a Mac 10.9.5. I got a message when I closed the program last night that said there was trouble backing up because of not enough space. I force quit, and then restarted my computer. I emptied my trash to free up some space. Now Lightroom will not open at all. Help!
If you force quit the lock file may not have been cleared on shutdown, this normally results in an error message on startup so might not be the case but is worth trying. The file is in the same folder location as your catalog.