Note that the credentials are not usable on sites that use forms-based logins, because the server will not return a 401 HTTP status to allow passing the network credentials. Instead, a 302 (Object moved) will occur, linking to the forms login page.

To get this scenario working in your app, you'll have to follow this (complex) scenario:

1. do a get of the requested page. if you are not logged in, the response will be a redirect header (302 probably).
2. do a get of the response url which should be the login page
3. parse the login page html for the username and password fields
4. post the field values to the login page.
5. if valid, you should get another redirect response with a cookie to use on future get/puts, and the url of the original page you requested. if the site is cookieless, you will get a munged url of the orginally requested page.
6. with the login cookie or munged url, you can now get your original page.