Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click

        Me.Button4.Enabled = False

        Dim myOldProcess As Process
        Dim allOldProcess As Process() = Process.GetProcessesByName("EXCEL")

        'ESEGUO EXCEL ---------------------
        Dim xlApp As New Excel.Application()
        Dim xlBooks As Excel.Workbooks = xlApp.Workbooks
        Dim xlBook As Excel.Workbook = xlBooks.Add
        Dim xlSheet As Excel.Worksheet = xlApp.ActiveSheet

        xlBook = xlApp.Workbooks.Open("D:\miofile.xls")
        xlSheet = xlBook.Worksheets(1)
        xlSheet.Activate()
        xlSheet.Range("A1").Value = "Hello Word"
        'xlSheet.Range("INDIRIZZO").Value = "INDIRIZZO"

        xlBook.Save()

        'xlBook.WebPagePreview()

        System.Threading.Thread.Sleep(3000)
        'fine EXCEL ---------------------

        Dim value As Boolean = False
        Dim killProcess As Integer

        Dim myNewProcess As Process
        Dim allNewProcess() As Process = Process.GetProcessesByName("EXCEL")

        If allOldProcess.Length = 0 Then
            For Each myNewProcess In allNewProcess
                killProcess = myNewProcess.Id
            Next
        Else
            For Each myNewProcess In allNewProcess
                Dim idProcess As Integer = myNewProcess.Id
                For Each myOldProcess In allOldProcess
                    If idProcess = myOldProcess.Id Then
                        value = False
                    Else
                        value = True
                    End If
                Next
                If value = True Then
                    killProcess = (myNewProcess.Id)
                End If
            Next
        End If

        Dim exlProcess As Process = Process.GetProcessById(killProcess)

        exlProcess.Kill()

        Me.Button4.Enabled = True

    End Sub