Do your logs store the user agent header? This header is an indication of the browser used to access the page. It's possible that the requests in question are coming from search engine indexers. At the same time, it's also possible that they are coming from browsers that don't support the HTTP_REFERER variables, or that are configured to not send it to the server.
FoxWeb Support Team
Sent by Jim on 08/06/2009 12:55:40 PM:
I have a foxweb script that invokes an iframe. I'll call it main.fwx for now. There is an IFrame in this script that calls sub.fwx for its content. One check I make to ensure that no one is attempting to call sub.fwx outside its parent page is to check to see if REQUEST.SERVERVARIABLES("HTTP_REFERER") equals "http://www.whatever.com/main.fwx". This worked great for some time. Then I began to notice that occassionally, HTTP_REFERER would be blank. Then it would start working again as before. This is all on the same system that hasn't seen any kind of upgrade to the web server or OS that coinsides with these events. And worse, most of the time it works fine. There's only one way to navigate to this page - it's one script that progreses through 4 steps and this occurs on step 3. Bookmarking or similar acts forces the view back to step 1 so I know it's not that.
Any guesses why HTTP_REFERER occasionally comes up empty?
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