VB.Net/Windows System/User
Current User Identity
Imports System.Windows.Forms
Imports System.Security.Principal
Imports System.Security.Permissions
Public Class SymEnc
    Public Shared Sub Main(ByVal CmdArgs() As String)
        Dim objIdentity As WindowsIdentity = WindowsIdentity.GetCurrent
        Dim objPrincipal As New Security.Principal.WindowsPrincipal(objIdentity)
        Console.WriteLine(objPrincipal.Identity.IsAuthenticated.ToString())
        Console.WriteLine(objIdentity.IsGuest.ToString())
        Console.WriteLine(objIdentity.ToString())
    End Sub
End Class
Get User Name
Imports System
Public Class MainClass
   Shared Sub Main()
        Console.WriteLine("UserName:           " & System.Environment.UserName)
   End Sub 
End Class
Is User Interactive
Imports System
Public Class MainClass
   Shared Sub Main()
        Console.WriteLine("UserInteractive:    " & System.Environment.UserInteractive)
   End Sub 
End Class