Wow! Such an old post but no real conclusion, which is a shame, because I have this problem:
I'm debugging a new app on my local pc. When I go into IIS and set the file security to "Integrated Windows Authentication" (for the page I'm working on only) everything is fine.
When I change the file security to Anonymous, the button click events do not fire.
Postback occurs and the Page Load event fires and you can step through using the debugger, but the button click event does not fire. it's not just that the debugger does not trap the event, the code actually does not run - changing the contents of a label for example does not work.
I change back to "Integrated Windows Authentication" and everything is fine again! WTF?
Any help appreciated.