Imports System.Runtime.InteropServices
Public Class Form1

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim objApp As SolidEdgeFramework.Application = Nothing
        Dim objDoc As SolidEdgePart.PartDocument = Nothing
        Dim objsym As SolidEdgeFrameworkSupport.SymbolicPMI = Nothing
        Dim objPMIGroup As SolidEdgeFrameworkSupport.SymbolicPMIGroup = Nothing
        Dim objPMI As SolidEdgeFrameworkSupport.PMI = Nothing
        Dim i As Integer

        Try
            ' Create/get the application with specific settings
            objApp = Marshal.GetActiveObject("SolidEdge.Application")

            ' Get the active JT document containing symbolic PMI group.
            objDoc = objApp.ActiveDocument
            ' Get PMI
            objDoc.PMI_ByModelState(PMIObj:=objPMI)
            'Get symbolic PMI Group
            objPMIGroup = objPMI.SymbolicPMIGroup
 
            i = objPMI.SymbolicPMIGroup.count()
            objsym = objPMIGroup.Item(1)
            objsym.Delete()

        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
End Class