Sub Test()
MsgBox "letzte Zeile aktives Arbeitsblat : " & ActiveLrw
MsgBox "letzte Zeile Tabelle2 : " & SheetLrw("Tabelle2")
MsgBox "letzte Zeile Mappe2, Tabelle1 : " & BookSheetLrw("Mappe2", "Tabelle1")
End Sub

Function ActiveLrw() As Long
ActiveLrw = Cells.Find("*", Cells(1), -4123, 2, 1, 2, False).Row
End Function

Function SheetLrw(Nm As String) As Long
   With Sheets(Nm)
      SheetLrw = .Cells.Find("*", Cells(1), -4123, 2, 1, 2, False).Row
   End With
End Function

Function BookSheetLrw(Bk As String, Nm As String) As Long
   With Workbooks(Bk).Sheets(Nm)
      BookSheetLrw = .Cells.Find("*", Cells(1), -4123, 2, 1, 2, False).Row
   End With
End Function