Running DNN 05.05.01, and AD Provider v5.0.2.  This is running on an IIS7.5 on Windows Server 2008 R2.

Everything appears to be working normally except the auto-creation of new user accounts on the DNN side.  We create a new user in Active Directory and they can not access the website.  I looked in the IIS logs and noticed lines regarding a 302 but not sure where to go from here.

Users are not logging in manually... they are just hitting the main site URL. For any pre-existing account, they get auto-logged onto the site via the AD provider.

I checked the log view on the portal, and nothing coming up.

IIS log repeated lines for this:
2010-11-24 23:28:43 172.20.2.187 GET / - 80 domain\test5 172.20.2.117 Mozilla/4.0+(compatible;+MSIE+7.0;+Windows+NT+6.0;+WOW64;+SLCC1;+.NET+CLR+2.0.50727;+.NET+CLR+1.1.4322;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+.NET4.0C;+.NET4.0E) 302 0 0 23

If I manually go to this URL with a new account,

http://dnn/DesktopModules/AuthenticationServices/ActiveDirectory/WindowsSignin.aspx

the page doesn't load... IE just spins and spins... looking at the IIS logs there it also appears to be trying do to a 302 for that URL:

2010-11-25 15:29:36 172.20.2.187 GET /DesktopModules/AuthenticationServices/ActiveDirectory/WindowsSignin.aspx - 80 domain\test5 172.20.2.117 Mozilla/4.0+(compatible;+MSIE+7.0;+Windows+NT+6.0;+WOW64;+SLCC1;+.NET+CLR+2.0.50727;+.NET+CLR+1.1.4322;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+.NET4.0C;+.NET4.0E) 302 0 0 52

I'm not doing impersonation, nor am I running with the classic app pool... not sure this is contributing to my problem.