new in the forum, new in webdesigh but not to programming, HTML or XML.

Still I have a bloody newbie question:

I signed up with a web-hoster (justhost) and the root directory is called
"public_html". I put my first index file there and voila - here is my start page.

Now I made a subfolder in this "public_html" and put another html file in there
that I want to access with WW.mysite.com/guestbook/guestbook.html.
(I cannot write www in this post)

But whatever I do, I always get the 404 page not found error if I want to access anything outside of the root folder...
Are there any permissions that need to be relaxed with teh hosting?

I am puzzled

Thanks for any pointers