สอบถาม ASP.net IIS5 (XP) ไม่สามารถอัพโหลดไฟล์ Excel ได้

    Private Sub BnImportDBNow_ServerClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles BnImportDBNow.ServerClick
        If Me.FileUpload1.HasFile Then
            '*** Create Excel.Application ***'
            Dim xlApp As New excel.Application
            Dim xlBook As excel.Workbook
            Dim xlSheet1 As excel.Worksheet
            Try
                Dim ChkFile As String = System.IO.Path.GetExtension(FileUpload1.FileName)
                If Not ChkFile.ToUpper = ".XLSX" Or ChkFile.ToUpper = ".XLS" Then
                    DisplayAJAXMessage(Page, "รองรับการอัพโหลดเฉพาะไฟล์ Excel(.xlsx, .xls)")
                    Exit Sub
                End If
                Dim MyConnection As System.Data.OleDb.OleDbConnection
                Dim DtSet As New DataTable
                Dim UlFileName As String
                UlFileName = "MyXls/" & System.IO.Path.GetFileName(FileUpload1.FileName)

                '*** Save Images ***'
                Errorss.InnerText = Server.MapPath(UlFileName)
                FileUpload1.PostedFile.SaveAs(Server.MapPath(UlFileName))


                Try
                    xlBook = xlApp.Workbooks.Open(Server.MapPath(UlFileName))
                    xlBook.Application.Visible = False
                    xlSheet1 = xlBook.Worksheets(1)
                Catch ex As Exception
                    Errorss.InnerText = "Error"
                End Try


                '*** Create DataTable ***'
                Dim DT As New System.Data.DataTable
                DT.Columns.Add("Itemcode", GetType(System.String))
                DT.Columns.Add("ItemName", GetType(System.String))
                DT.Columns.Add("Unitcode", GetType(System.String))
                DT.Columns.Add("QTY", GetType(System.Double))
                DT.Columns.Add("WHCODE", GetType(System.String))
                DT.Columns.Add("GroupCount", GetType(System.Double))
                Dim MyCommand As System.Data.OleDb.OleDbDataAdapter
                MyConnection = New System.Data.OleDb.OleDbConnection("provider=Microsoft.Jet.OLEDB.4.0;Data Source='" & Server.MapPath(UlFileName) & "';Extended Properties=Excel 8.0;")
                MyCommand = New System.Data.OleDb.OleDbDataAdapter("select * from [Sheet1$]", MyConnection)
                MyCommand.Fill(DtSet)
                For i As Integer = 0 To DtSet.Rows.Count - 1
                    MsgBox(DtSet.Rows(i).Item("Itemcode") & " " & DtSet.Rows(i).Item("ItemName") & " " & DtSet.Rows(i).Item("Unitcode") & " " & DtSet.Rows(i).Item("QTY"))
                Next
                xlApp.Application.Quit()
                xlApp.Quit()
                xlSheet1 = Nothing
                xlBook = Nothing
                xlApp = Nothing
                DisplayAJAXMessage(Page, "อัพโหลดข้อมูลเรียบร้อยแล้ว")
            Catch ex As Exception
                DisplayAJAXMessage(Page, "เกิดข้อผิดพลาดระหว่างบันทึก กรุณาลองใหม่อีกครั้ง")
                xlApp.Application.Quit()
                xlApp.Quit()
                xlSheet1 = Nothing
                xlBook = Nothing
                xlApp = Nothing
                Exit Sub
            End Try
        Else
            DisplayAJAXMessage(Page, "กรุณาเลือกไฟล์ Excel ที่จะอัพโหลด")
            Exit Sub
        End If

    End Sub