I have DNN Community Edition Version: 06.02.00 (1610) installed; no errors; portal dnn.  I have installed the latest version of the AD provider as well.   App Pool is using .Net 2.0 Integrated with NetworkService as the identity.

After initially entering http://mydomain.com/dnn, I'm redirected to the following URL followed by a 500 error: 

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

If I enter http://mydomain.com/dnn again, I'm presented with the DNN login dialog page with my choice of Standard or Windows login.  Both methods work fine.  DNN logs in both Host & Admin accounts and Windows authenticates users from my AD domain.  So DNN & AD authentication is working.

Any ideas on why I'm getting this 500 error on WindowsSignin.aspx?  I've read "millions" of posts but have not found a clear positive remedy.

Thanks!

Mark;

1st thing to check is where you are actually pointing IIS to pick up the files?

Here's a Microsoft KB article that should help you troubleshoot what your issue is:

http://support.microsoft.com/kb/942031

Try getting rid of 1 of PageHandlerFactory-ISAPI-2.0 .....Executable =%windir%\Microsoft.NET\Framework\v2.0.50727\aspnet_isapi.dll

In a half dozen Win2008 and Win2008R2 installs I only have 1 of those handlers...

Make sure you copy off the path, Exectuable and Name information first in case you need to re-create it later...

Restart IIS and retry the site..