I cannot launch the organizer from the PSE from the home window. The "Loading the Elements Organizer Workspace" message shows but nothing happens. I tried loading it by going to the exe file but that doesn't work either.
Hold down the Shift key while launching the Organizer. This should bring up the Catalog manager. Select your catalog and use the Optimize and Repair buttons. This may take a while, depending on the size of your catalog. Once those procedures are completed, try opening the catalog. If that doesn't work, create and open a new catalog. Once the Organizer is open, go back to the File>Manage Catalogs dialog and try to open the old catalog.