This code crash systematically SolidWorks:

Dim swApp As SldWorks.SldWorks

Sub main()
    Set swApp = Application.SldWorks

    Dim swRootModel     As SldWorks.ModelDoc2: Set swRootModel = swApp.ActiveDoc
    Dim i               As Integer
    Dim swFeat          As SldWorks.Feature
    Dim swMirrorFeat    As SldWorks.MirrorPartFeatureData

    If swRootModel Is Nothing Then Exit Sub

    For i = 0 To swRootModel.GetFeatureCount - 1
        Set swFeat = swRootModel.FeatureByPositionReverse(i)

        If Not swFeat Is Nothing Then
            'Debug.Print swFeat.Name & " [" & swFeat.GetTypeName & " / " & swFeat.GetTypeName2 & "]"
            If swFeat.GetTypeName = "MirrorStock" Then
                Debug.Print "[*] NAME: " & swFeat.Name

                Set swMirrorFeat = swFeat.GetDefinition
                If Not swMirrorFeat Is Nothing Then
                    Debug.Print "  [*] AbsorbedSketches     : " & swMirrorFeat.AbsorbedSketches
                    Debug.Print "  [*] Axes                 : " & swMirrorFeat.Axes
                    Debug.Print "  [*] CoordinateSystems    : " & swMirrorFeat.CoordinateSystems
                    Debug.Print "  [*] CosmeticThreads      : " & swMirrorFeat.CosmeticThreads
                    Debug.Print "  [*] CustomProperties     : " & swMirrorFeat.CustomProperties
                    Debug.Print "  [*] CutListProperties    : " & swMirrorFeat.CutListProperties
                    Debug.Print "  [*] DimXpertAnnotations  : " & swMirrorFeat.DimXpertAnnotations
                    Debug.Print "  [*] HoleWizardData       : " & swMirrorFeat.HoleWizardData
                    Debug.Print "  [*] ModelDimensions      : " & swMirrorFeat.ModelDimensions
                    Debug.Print "  [*] PathName             : " & swMirrorFeat.PathName
                    Debug.Print "  [*] Planes               : " & swMirrorFeat.Planes
                    Debug.Print "  [*] SheetMetalInformation: " & swMirrorFeat.SheetMetalInformation
                    Debug.Print "  [*] SolidBodies          : " & swMirrorFeat.SolidBodies
                    Debug.Print "  [*] SurfaceBodies        : " & swMirrorFeat.SurfaceBodies
                    Debug.Print "  [*] UnabsorbedSketches   : " & swMirrorFeat.UnabsorbedSketches
                    Debug.Print "  [*] UnlockedProperties   : " & swMirrorFeat.UnlockedProperties

                    'swMirrorFeat.AbsorbedSketches = False
                    'swMirrorFeat.Axes = False
                    'swMirrorFeat.CoordinateSystems = False
                    'swMirrorFeat.CosmeticThreads = False
                    'swMirrorFeat.CustomProperties = False
                    'swMirrorFeat.CutListProperties = False
                    'swMirrorFeat.DimXpertAnnotations = False
                    'swMirrorFeat.HoleWizardData = False
                    'swMirrorFeat.ModelDimensions = False
                    'swMirrorFeat.PathName
                    'swMirrorFeat.Planes = False
                    'swMirrorFeat.SheetMetalInformation = False
                    'swMirrorFeat.SolidBodies
                    'swMirrorFeat.SurfaceBodies = False
                    'swMirrorFeat.UnabsorbedSketches = False
                    'swMirrorFeat.UnlockedProperties

                    swMirrorFeat.AccessSelections swRootModel, Nothing
                    swFeat.ModifyDefinition swMirrorFeat, swRootModel, Nothing
                    swMirrorFeat.ReleaseSelectionAccess

                    'swFeat.Select2 False, 0
                    'Set swFeat = swRootModel.SelectionManager.GetSelectedObject6(1, -1)
                    'Set swMirrorFeat = swFeat.GetDefinition
                    'swMirrorFeat.AccessSelections swRootModel, Nothing
                    'swFeat.ModifyDefinition swMirrorFeat, swRootModel, Nothing
                    'swMirrorFeat.ReleaseSelectionAccess

                    Exit Sub
                End If
            End If
        End If
    Next i
End Sub
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 The problem is this line:

swFeat.ModifyDefinition swMirrorFeat, swRootModel, Nothing‍

There is a method to update Mirrored Part ?

Thanks.