get The local Mac Address

 Dim mc As ManagementClass
        Dim moc As ManagementObjectCollection
        Dim mo As ManagementObject
        mc = New ManagementClass("Win32_NetworkAdapterConfiguration")
        moc = mc.GetInstances() ' Get all network adapter instances
        For Each mo In moc
       If mo.Item("IPEnabled") = True Then
           TextBox1.Text = mo.Item("MacAddress").ToString()
       End If
       mo.Dispose()
        Next

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