error 3259 when adding a record with attachment (1 Viewer)

Private Sub add_tune()
 
   Dim dbtune As DAO.Database
   Dim rst_tune As DAO.Recordset
   Dim rst_tune_in As DAO.Recordset
   Dim rs_child As DAO.Recordset
 
 
   Set dbtune = CurrentDb
   Set rst_tune = dbtune.OpenRecordset("tbl_tune")
   Set rst_tune_in = dbtune.OpenRecordset("source_data")
   rst_tune_in.MoveFirst
 
 
   Do Until rst_tune_in.EOF = True
 
      rst_tune.AddNew
      rst_tune("t_title").Value = rst_tune_in("title")
 
      file_string = "G:\sibelius\scores\volksmuziek\dans\branl1.jpg"
 
      [COLOR=black]rst_tune.Fields("t_first_bars").LoadFromFile file_string[/COLOR]
 
      rst_tune("t_stamp").Value = Now()
      rst_tune.Update
 
      rst_tune_in.MoveNext
 
   Loop
 
   rst_tune.Close
   rst_tune_in.Close
 
   Set rst_tune = Nothing
   Set rst_tune_in = Nothing
End Sub

      rst_tune.AddNew
      rst_tune("t_title").Value = rst_tune_in("title")
 
      file_string = "G:\sibelius\scores\volksmuziek\dans\branl1.jpg"
 
      't_jpg is a field with data type "attachment" in table rst_tune
 
     Set rsPictures = rst_tune.Fields("t_jpg").Value
     'so rsPictures points to field t_jpg and is not a (visible?) table in the database   
 
   ' Add a new attachment.
     rsPictures.AddNew
 
     'FileData is a reserved word in Access and is not the name of a field in
    ' one of the user defined tables
      rsPictures.Fields("FileData").LoadFromFile file_string
      rsPictures.Update
 
      rst_tune.Update