Windows authentication problem

Hi.

First time deploying a site to IIS.

 Im trying String username=System.Security.Principal.WindowsIdentity.GetCurrent().Name.

 

It works fine when im running locally and it shows my name just fine. However when i deploy on our server IIS my name is suddenly NT AUTHORITY/NETWORK SERVICE

I have disabled <enable anonymous access>

I have enabled Integrated Windows authentication for my website on the IIS

 

Any tips much appreciated :-)
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