The disk clean up manager, and the all the default handlers registred.
The clean up handler configration dialog.
you'll see this dialog for only when you register the server for the first time.
you'll get to define a directory to set this handler.
seperate each extension with a semicolon ;
when you click on the button, you can see all the files that will be deleted by the handler.
you can uncheck the clean handler from the list, to not delete the files.