I have two ASP.NET pages, say page1 and page2.

Page1 contains an update panel and I use AJAX History to allow browser back/forward button support. Users can navigate to page2 via page1 - I do a response.redirect server-side so that I can store in a session what options were on page1 when they left. On page2, a user can click the back button and return to page1 with it displaying what was there prior to navigating to page2. You can click the back button again on page1 to go back to other selectively chosen history states.

This all works great in IE8, Firefox, Safari, and Chrome. However, in IE7 it doesn't. The user can get back to page1 from page2, but when they click the back button again it doesn't show the previous states of page1 - it displays the original page load content. The history data looks to still be encoded in the url when using ie7 but is not working for some reason.

Does anyone know why this is happening in IE7 and how I can get around this? It really needs to work in IE7 as most of our users are on IE7. Please help.