Did you see the example & explanation in the link I gave? I think that gives a reasonable description about how to create one. What is it? Um ... it's the details of the hashtree of the file plus the user's ip address. So, if someone types the link into their browser, it will open LW & start downlding that file from you. To create it, it also involves your browser. Click on the link I gave above & see the last post in that thread. By the way, that thread is a Sticky & is listed at the top of this section of the forum.