Based on everything I've been able to google up on using AD authentication with DNN7, Server2k8r2, iis7.5, it is not possible to configure auto-login in this configuration with the current provider.  If I've read correctly, the AD provider requires classic mode in the app pool to successfully execute auto-login, but dnn7 requires integrated mode.  Is this correct?  Can anybody confirm this?

AD authentication definitely works on DNN7, but auto-login is not possible with the 5.0.4 provider as far as I can tell.  If this is the case, it would be helpful for the AD provider team to post this in big bold text on the codeplex page so that people like me don't spend hours trying to make it work. I'm just saying...

Tim, the AD provider does work under the integrated pipeline with some configuration changes that are explained in the readme when you install the provider and in the documentation (IIS Settings IIS 7.x Integrated Pipeline Mode Setup) http://dnnauthad.codeplex.com/documen...

Tim and Mike - However, with the above said, it looks something may have changed in the core code on one of the point releases as the autologin was working just fine with early versions of DNN 7. I've just setup a fresh test site on my 2008 R2 server and can verify that autologin is not working. I'll have to do some testing to see if it reacts the same on a W7 setup as that's what I use for development. I'll keep you posted.

Tim and Mike. I've figured out what the problem is and a work around until I can get a permanent fix.

Explanation of problem:
I'm guessing that you never entered anything in the Auto-login IP Address entry. It looks like that's where the problem is originating. In previous versions of DotNetNuke if an attempt was made to look up a portal setting and it didn't exist then it just returned a null value. In DNN 7 it actually throws an error. So if nothing was entered as the Auto-login IP it throws and error and exits the procedure before it can load the Searchbot configuration. In the code that checks the search bot line the string was empty so it exited that procedure thus never getting redirected to windowssignin.aspx.

Workaround:
Go into the provider settings and enter 127.0.0.1 in the auto-login IP section and then update the settings. You can then go back in and remove that line in the settings and then again update. Clear the cache and cookies and you should auto login should now work. If you go to http://addnn7.hortonfamily.ca you should get the IIS popup to show you that this does indeed work.