Imports System.Security.Principal

Public Class Form1
Public id As WindowsIdentity = WindowsIdentity.GetCurrent()
Public User As WindowsPrincipal = New WindowsPrincipal(id)

Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Dim flg As Boolean = User.IsInRole(“Domain\Security Group”)

Select Case flg
Case True
MsgBox(“I am a member of the group”)
Case False
MsgBox(“Not a member”)
End Select

End Sub

End Class