Accessing files and directories

I am having trouble understanding exactly how to overcome an access problem. I have read a couple of articles on authentication (eg Julie Meloni on Zend) but I do not really want to use the standard log-in dialog box that seems to be used in all of the examples I've seen. I have two part log-in form (for two user types) and authenticate the user entered name and password from a database. This bit works OK and the user is passed to the relevant page. However clicking a link on that page which runs another php file results in the authentication dialog box being shown. I assume that this happens because I have protected the directory where all my php scripts reside using .htaccess and .htpasswd to prevent access to the scripts (not that they're worth stealing!). What I can't grasp is why the first page after log-in (which is in the protected directory) is displayed without the authentication dialog being shown, yet moving from this page to another requires authentication. I know someone will suggest sessions and I am considering them, but as yet I don't think my server (Hurricane Electric) has PHP4 installed. At least a test with session_start() failed and I have not had a reply to my question from their support. Sorry this is long winded but any help/advice much appreciated. Mick Lloyd mjl@consultingrooms.com