I have a website that has ASP.Net Impersonation Enabled and Windows Authentication Enabled. When navigating to that site using IE8 with "Enable Integrated Windows Authentication" (under Tools -> Internet Options -> Advanced) checked, the browser pops-up a "Windows Security" dialog box asking for User name and Password. My understanding was that this was automatically passed through and I would not need to type in those details.
Additional Information:
If I uncheck "Enable Integrated Windows Authentication" I do not get the pop-up window and it appears to work was intended (though that is the opposite of what I would be expecting)
If I enable Windows Authentication in Firefox I do not get the pop-up window (i.e. works as intended)
Are there some settings or similar that could have been set to create this behavior? Or has anyone else seen similar behavior and know how to fix?