Page.User.Identity.Name;

I have 2 questions:

1.) Why is it that this line of code does not show up in run-time. I have a tab container that contains 2 panels. Does this matter why it will not show cause if I hard code the string "hello world" it shows plus I placed that code on a blank page and it showed my compouter name. Why is it that it will not show on my usercontrol.ascx page with 2 tabs.

lblRole.Text = Page.User.Identity.Name;

2.) When I tested number one on a blank page it shows my computer name how do I get it to show windows user login id?
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