This site is currently Unavailable

The Active Directory Provider requires the site to be running

under Full Trust and/or in Classic mode in IIS 7.0

Commenting out the line:

<add name="Authentication" type="DotNetNuke.Authentication.ActiveDirectory.HttpModules.AuthenticationModule, DotNetNuke.Authentication.ActiveDirectory" />

in your web.config will allow you to get the site running until it meets the above requirements.