Ueli, if you have your internal IPs then all you need to do is have that range entered in the Auto Login IP Address section. External users will not get redirected to WindowsSignin.aspx then.

I understand that Ueli. What I'm saying is that if the internal IP range is set then internal users hitting either domain should be automatically logged in while anyone hitting them from an external IP will just be directed to the home page. The only time I've seen this go sideways was if there was an appliance between the outside and the server that changed the external IPs to an internal one.

As for setting up domain names to either autologin or not would be an enhancement. You can log it in Gemini @ http://support.dotnetnuke.com.

I've found a quick but dirty workaround.

In DesktopModules\AuthenticationServices\ActiveDirectory\WindowsSignin.aspx just change the Text in the plsetIIs from "Error while processing Windows..." to a javscript part thats reloads the page again.

e.g. windows.location.href='http://yourdomain.com'

At the first time the cookie is not valid and dnn executes the js. On the second request the cookie is valid and the ad-provider lets you enter the page. (I thinks that's what happens.) If not, well I it works and that's what is important to me :-)

With this method you can even choose an other entry page for unregistered user by setting the fitting url-parametes in your uri.

Of course Javascript will then be requiered.