I don't think you can do this by altering any of the server settings. The only way I can think of doing it is to create an ASP page that users will go to to browse files. You can then control which files they see using the FileSystem Object. Since each file has a name (File.Name), you can assign a variable and then pick up any periods that are within that string, working from the right to the left (since file names themselves can contain periods, not just the .extension). Give it a try.