Dim oInvApp As Inventor.Application = Nothing
oInvApp = CreateObject("Inventor.Application")

    Private Function GetInventorInstances() As Collection
 
        Dim iIndex As Integer = 0
 
        Dim listInstances As New Collection
 
        Try
            Dim ROTObject As Object = Nothing
            Dim runningObjectTable As IRunningObjectTable
            Dim monikerEnumerator As IEnumMoniker = Nothing
            Dim monikers(1) As IMoniker
 
            runningObjectTable = GetRunningObjectTable(0)
            runningObjectTable.EnumRunning(monikerEnumerator)
            monikerEnumerator.Reset()
 
            Dim numFetched As IntPtr = New IntPtr()
            While (monikerEnumerator.Next(1, monikers, numFetched) = 0)
                Dim ctx As IBindCtx
                ctx = CreateBindCtx(0)
 
                Dim runningObjectName As String = ""
                monikers(0).GetDisplayName(ctx, Nothing, runningObjectName)
 
                runningObjectName = runningObjectName.ToUpper
                If (Not runningObjectName.Equals("")) Then
                    Dim runningObjectIns As Object = Nothing
                    runningObjectTable.GetObject(monikers(0), runningObjectIns)
 
                    Try
                        Dim oInvIns As Inventor.Application = Nothing
                        oInvIns = DirectCast(runningObjectIns, _
                          Inventor.Application)
 
                        'woher weiss ich jetzt welche instanz ich hier habe?
 
                        iIndex += 1
                        listInstances.Add(oInvIns, iIndex)
                    Catch ex As Exception
                    End Try
                End If
            End While
 
        Catch ex As Exception
        End Try
 
        Return listInstances
 
    End Function

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