Use windows authentication to check in Active Directory

Hi,

        I am developing a Intranet web application in ASP.NET.I have to use windows authentication to

check if the user exists in the active directory.If the user exists in active directory then they are

authenticated to use the application.

1.I checked the Integrated windows authentication is IIS

2.I have set the authentication mode to windows in web.config.

3.I am also able to display the user name (i.e the user name of the windows login) at page_load

But I don't know how to check if that particular user exists in the active directory.

Please guide me.

 

Thanks,

pcs

 

 
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