Dim oExcel As Object = Nothing
        Dim oBook As Object = Nothing
        Dim oSheet As Object = Nothing
        Try
            oExcel = GetObject(, "Excel.Application")
        Catch ex As Exception
            Try
                oExcel = CreateObject("Excel.Application")
            Catch ex1 As Exception
                MsgBox("Applikation nicht installiert!", _
                    MsgBoxStyle.Critical, "Error")
            End Try
        End Try
        oExcel.Visible = True ' zu Testzwecken
        oBook = oExcel.Workbooks.Open("F:\Protokoll.xlsx")
        oSheet = oBook.Worksheets("Seite 1")
 
 
        oSheet.Range("C2").Value = txtC2.Text
.
.
.Hier kommen jetzt gaaaanz viele einzelne Zellen, welche auf obige weise _
  gefüllt werden...
.
.
. 
Try
            oBook.SaveAs("F:\Protokoll.xlsx")
        Catch
            MsgBox(Prompt:="Datei bereits Vorhanden")
        End Try
 
        If chkAnzeigen.Checked = False Then
            oBook.Close(True)
            oExcel.Quit()
        End If
        oSheet = Nothing
        oBook = Nothing
        oExcel = Nothing
        GC.Collect()
        GC.WaitForFullGCComplete()

  Sub Main()
        ' Create an Outlook application.
        Dim oApp As Outlook._Application
        oApp = New Outlook.Application()
 
        ' Create a new MailItem.
        Dim oMsg As Outlook._MailItem
        oMsg = oApp.CreateItem(Outlook.OlItemType.olMailItem)
        oMsg.Subject = "Send Attachment Using OOM in Visual Basic .NET"
        oMsg.Body = "Hello World" & vbCr & vbCr
 
        ' TODO: Replace with a valid e-mail address.
        oMsg.To = "user@example.com"
 
        ' Add an attachment
        ' TODO: Replace with a valid attachment path.
        Dim sSource As String = "C:\Temp\Hello.txt"
        ' TODO: Replace with attachment name
        Dim sDisplayName As String = "Hello.txt"
 
        Dim sBodyLen As String = oMsg.Body.Length
        Dim oAttachs As Outlook.Attachments = oMsg.Attachments
        Dim oAttach As Outlook.Attachment
        oAttach = oAttachs.Add(sSource, , sBodyLen + 1, sDisplayName)
 
        ' Send
        oMsg.Send()
 
        ' Clean up
        oApp = Nothing
        oMsg = Nothing
        oAttach = Nothing
        oAttachs = Nothing
    End Sub