Show documents in hidden directories'. Close all pages. Open Folders View. Your theme is gone. Close all pages.
Open Folders View.
From the scroll window select the desired theme. Check the appropriate Vivid Color, Active Graphics and Background Picture. Or you can at least determine where in your web the problem lies, and fix it. Hopefully you will be able to identify the page or pages that are giving you problems. If this fails and themes are important, click on Hosts, FP2000 .