xlBlattP.Range("E" & Zp - 1).FormulaR1C1 = "=Massen!R[" & Zl - 2 - Zp & _
   "]C[19]"

Public Function erstelle_Xl_WB_Massen(ByVal SPath As String, ByVal Filename As _
  String) As Boolean
        Dim xlApp As Microsoft.Office.Interop.Excel.Application
        Dim xlMappe As Microsoft.Office.Interop.Excel.Workbook = Nothing
        Dim xlBlattM As Microsoft.Office.Interop.Excel.Worksheet = Nothing
        Dim xlBlattP As Microsoft.Office.Interop.Excel.Worksheet = Nothing
        Dim Zl As Integer = 1, Zp As Integer = 1
        xlApp = New Microsoft.Office.Interop.Excel.Application
        xlMappe = xlApp.Workbooks.Add   '  New 
        ' Microsoft.Office.Interop.Excel.Workbook
        xlBlattP = xlMappe.Worksheets(1)  'xlMappe.Worksheets.Add
        xlBlattP.Name = "Kurztext"
        xlBlattM = xlMappe.Worksheets(2)   'xlMappe.Worksheets.Add
        xlBlattM.Name = "Massen"
        Dim ColArr() As String                    ' Array für die 
        ' Spaltenbreiten (22)
        ReDim ColArr(8)
        Call Fill_WSk_ColArr(ColArr)                ' definiert die 
        ' Spaltenbreiten des WSk
        If XL_WsP_Header(xlBlattP, ColArr, Zp) = False Then GoTo Fehler
        ReDim ColArr(22)
        Call Fill_WSm_ColArr(ColArr)                ' definiert die 
        ' Spaltenbreiten des WSm
        If XL_WsM_Header(xlBlattM, ColArr, Zl) = False Then GoTo Fehler ' Header
        For i As Integer = 0 To UBound(vntGAEB, 1)
            If vntGAEB(i, 0) = "POSITION" Then
                Dim OZex As String = vntGAEB(i, 1)                          ' 
                ' OZ-Nummer aus der Position
                Dim KTex As String = vntGAEB(i, 7)                          ' 
                ' Kurztext zur Position
                Dim Einh As String = vntGAEB(i, 4)                          ' 
                ' Einheit zur Position
                Dim EP As String = vntGAEB(i, 5)                            ' 
                ' Einheit zur Position
                Dim BeginnPos As Integer = 2
 
                Dim OZView As DataView = New DataView(DirectCast( _
                  Hauptform.BsMassen.DataSource, DataTable), "OZ = '" & OZex & _
                  "'", "Adresse ASC", DataViewRowState.CurrentRows)
                If OZView.Count > 0 Then                                    _
                ' Wenn es Daten zur OZ gibt
                    ' Datenzeilen der OZ
                    Dim MassenBeginn As Integer = Zl
                    If Xl_WsM_Add_RowOZ(xlBlattM, OZex, KTex, Zl) = False Then _
                      GoTo Fehler ' Beginn Positione
                    BeginnPos = Zl                                              _
                                ' zum späteren Summieren
                    For Each ViewRow As DataRowView In OZView                   _
                                ' jeden Datensatz zur OZ
                        If Xl_WsM_Add_RowData(xlBlattM, ViewRow, Einh, Zl) = _
                        False Then GoTo Fehler ' Datenzeile
                    Next
                    If XL_WsM_Add_RowSumm(xlBlattM, OZex, BeginnPos, Zl) = _
                      False Then GoTo Fehler ' Summenzeile
                    Dim ZlDiff As Integer = Zl - 2 - Zp
                    Dim ColDiff As Integer = 19
                    xlBlattP.Range("E" & Zp - 1).FormulaR1C1 = "=Massen!R[" & _
                      Zl - 2 - Zp & "]C[19]"
                    xlBlattP.Range("E" & Zp - 1).Formula = "=Massen!S" & Zl - 2 _
                    & " ' Formel auf Ergebnis setzen"
                End If
            Else
                Debug.Print(vntGAEB(i, 0))
                Select Case vntGAEB(i, 0)
                    Case "GRP"
                        If XL_WsP_Add_RowOZ(xlBlattP, i, Zp) = False Then GoTo _
                          Fehler
                End Select
            End If
        Next
        Try
            xlMappe.SaveAs(SPath & "\" & Filename & ".xls")
        Catch ex As Exception
            GoTo Fehler
        End Try
        xlBlattP = Nothing
        xlBlattM = Nothing
        xlMappe = Nothing
        xlApp = Nothing
        Return True
Fehler:
        xlBlattP = Nothing
        xlBlattM = Nothing
        xlMappe = Nothing
        xlApp = Nothing
        Return False
    End Function

Danke für die Hilfe

Gruß Christian