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?