I just spent a few hours debugging something that I finally tracked down to IE and Firefox dealing with HTTP caching differently. To make a very *long* story short (and believe me, this was a story of hours in Firebug and Fiddler and VS), IE does *not* cache HTTP pages if you send down the no-cache directive. Firefox does not cache HTTPS pages but *caches* HTTP responses even if you send down a no-cache. The fix is simple - send down a no-store directive instead. So instead of
Cache-Control no-cache
you send down
Cache-Control no-store
I eventually found a Bugzilla bug which deals with this exact scenario. It seems to be a contentious issue with different opinions on what the right behaviour should be. I'm just happy that I get to fix it with just a one-line code change :-)
Response.Cache.SetNoStore();
I'm putting it out there so that some poor soul in the future can save some time. :-)
