SketchManager::MakeSketchBlockFromFile Return Value =Nothing

Hello,

     When I insert the same sketch block, always get an empty return value.

     I have tried many ways. But no one will work.

     Anyone can help me?

     My Code is below:

  Public Sub InsertPlugView(PtX As Object, PtY As Object, PtZ As Object, objPlugBlockPath As Object, objPlugBlockNbr As Integer)

        Dim swDoc As ModelDoc2 = Nothing

        Dim swPart As PartDoc = Nothing

        Dim swDrawing As DrawingDoc = Nothing

        Dim swAssembly As AssemblyDoc = Nothing

        Dim boolstatus As Boolean = False

        Dim longstatus As Integer = 0

        Dim longwarnings As Integer = 0

        Dim swSketchBlockDef As SketchBlockDefinition

        Dim plugPt(0 To 2) As Double

        Dim objPlugPt As Object

        Dim swSkBlockNm As String

        Dim MathUtility As MathUtility

        Dim swMathPt As MathPoint

        Dim swBlockInst As SketchBlockInstance

        swApp = GetObject(, "SldWorks.Application")

        swApp.SetUserPreferenceToggle(swUserPreferenceToggle_e.swSketchInference, False)

        swDoc = swApp.ActiveDoc

        swDrawing = swDoc

        boolstatus = swDrawing.ActivateSheet("Sheet1")

        For i = 0 To objPlugBlockNbr - 1

            swSkBlockNm = Application.StartupPath + objPlugBlockPath(i)

            plugPt(0) = Val(PtX(i)) : plugPt(1) = Val(PtY(i)) : plugPt(2) = Val(PtZ(i))

            objPlugPt = plugPt

            MathUtility = swApp.GetMathUtility

            swMathPt = MathUtility.CreatePoint (objPlugPt)

            'Insert Block

            swSketchBlockDef = swDoc.SketchManager.MakeSketchBlockFromFile(swMathPt, swSkBlockNm, False, 1, 0)

            'swSketchBlockDef =Nothing error!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

        

             swBlockInst = swSketchBlockDef.GetInstances()(0)

            'Explode Block

            swDoc.SketchManager.ExplodeSketchBlockInstance(swBlockInst)

            swDoc.SetPickMode ()

            swDoc.ClearSelection2(True)

        Next i

    End Sub

SolidworksApi macros