Prevent users using the back button.

[eluser]kurucu[/eluser]
You could also send the nocache headers, I think, so that pages are always requested.

Really you can't stop users pressing "back", that's their decision not yours. However
- as stated, some javascript would definitely be able to help (although annoying for your user)
- definitely secure all actions on the controller
- other options include using POST data for all actions so that the browser refreshes the page, or
- post secure pages through a redirect... thus the browser would re-request the redirecting controller on pressing back, and not the viewed page before it.
- HTTPS doesn't cache, as far as I know, so you could switch to that

No real nice solutions, I think the nocache is the cleanest but will enhance your server load.

Also, different browsers do different things, so read up on stopping caches well!