username and password

Thank you for your question. You cannot get password. User Name only. You can impersonate Windows XP user for .NET application by the bellow code.

System.Security.Principal.WindowsImpersonationContext impersonationContext;
impersonationContext = 
    ((System.Security.Principal.WindowsIdentity)User.Identity).Impersonate();

//Insert your code that runs under the security context of the authenticating user here.

impersonationContext.Undo();

Thanks,
Mamun