Seems to have lost all of my custom components?

I’ve created a number of parts which were not in the Upverter database in order to complete projects. They’ve been on my boards for a while. Today, all of my custom parts still show up in my Library, but when I attempt to place them, I get a “Page not found” error. This seems to happen with all of the parts I’ve created. Any advise would be helpful, before creating all of the parts again.