Regarding the X-Frame-Options (https://developer.mozilla.org/en-US/docs/The_X-FRAME-OPTIONS_response_header), I'm having a bit of a hard time parsing what the docs say and what I'm seeing. My understanding is that when the page returns SAMEORIGIN, browsers will only load the contents of the frame if the page that had the IFRAME came from the same domain.
I've got three machines. When I'm logged into SERVER-A, I navigate to a page that is hosted on SERVER-A. It contains an IFrame that loads a page from SERVER-B but it's in a different domain. This all works... but when I go to SERVER-C and browse to the same page (that's served from SERVER-A), it won't load. Looking at the IE Debugging Tools, the request for that IFramed page shows a status of aborted.
Ideas?