integrated windows authentication

I created a new aps.net (1.1) project. By setting anonymous authentication in IIS, I am able to browse the page as:http://localhost/testapp/test.aspx and http://localhost.abc.local/testapp/test.aspx. In my host file, I do have localhost.abc.local mapped to 127.0.0.1, just as localhost.

Since I need to retrieve the user id on the page, I want to use integrated windows authentication. So I disabled the anonymous in IIS. Now  http://localhost/testapp/test.aspx  works fine, but when I try to go http://localhost.abc.local/testapp/test.aspx, it says I am not authorized to access the page.

Any idea why? 

 

 
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