Windows Authentication doesn't prompt for login

Question

I've had Windows Authentication setup on an area of our website for some time now, and it has worked flawlessly so far. Recently, the login prompt stopped appearing and went straight to "Page cannot be displayed" for some reason. While connected to our network, the page works fine. Outside our network, users are supposed to receive a login prompt but they now do not, instead receiving the "page cannot be displayed" error.

Why would this suddenly occur, and how is it fixed? I have tried removing the virtual directory and re-adding it but nothing seems to work.

The strange thing is this is only happening in IE - Google Chrome works fine (I receive the login prompt).

Is there a setting or something inside of IIS that disables this login prompt or something? It is strange it is an IE specific issue as well - there were no changes to the state of IE from one day when it was working to the next where it wasn't.

Anyone have ideas on what might be causing this?

Thanks

Answer 1

there is a checkbox in internet options->advanced tab to enable/disable Windows Authentication but you said that there were no changes. either way it is something to check

Answer 2

It sounds like you are hitting a security setting in IE.

IE stops windows authentication information from being sent to sites that you do not trust.

You could try adding the site to your list of trusted sites.

Answer 3

Oddly enough, I'd wonder why you were getting the login prompt before now.

If you're logged in to Windows and the site you're browsing to uses Windows Auth, IE will automatically try to pass the logged in user's credentials to the site (this all depends on your domain configuration/trust setup...something may have changed with those settings at the domain level that changed the behavior of your IE).

Chrome/Firefox/Safari don't have this functionality, which is why you're still getting a login prompt.

Answer 4

You can start by taking a network trace both Internally and Externally, reproduce the issue and see if the request actually reaches the web server. Also, check the IIS logfile for the "Page Cannot Be Displayed" response.

Let me know if that helps or if you have more questions.

Regards, Vivek.

Answer 5

You need to take a network capture (www.fiddlercap.com) to get any real help with this.

IE supports the "Negotiate" protocol in addition to NTLM; Chrome and other browsers typically only support NTLM.