AD / Forms authentication

I am developing an application that will mainly be used internally and want to know how i can automatically authenticate users against Active Directory without prompting them to login.

However, when a user is not automatically authenticated (i.e. they have connected via the internet) I want to display a form that 开发者_如何学JAVAwill authenticate the user against AD

Can anyone help ?

In terms of ASP.NET you want to mix Windows and Forms Authentication. There is no simple solution. The possible workarounds are already discussed here:

Mixing Windows Authentication with Forms Authentication