I have an older website (developed in VS2005, .net 2.0) that has uses an asp:treeview and asp:calendar controls with an Ajax AsyncPostBack trigger to refresh an update panel based on the treeview node/calendar date selected.
We've been having a problem with an increasing number of users reporting these screens not working, and have tracked the problem down to a security update released on July 9. (KB2846071) Website works fine BEFORE update is applied, and is broken after update is applied.
The "broken" behavior is that the control does a full-page postback every time, instead of asynchronously, so the user just sees the screen "flash" and nothing actually changes.
The page is pretty complicated and makes significant use of the benefits of updatepanels, so I'm at a loss as to how to resolve this...?