Private Sub Grid1_AfterUpdate(ByVal nRow As Long, ByVal nCol As Long, ByVal _
  sText As String)
......
 
If nCol = .GetCol("ArtikelNr") Then
  dRabatt = rabatt_check(tb_Produkte!ArtikelNr)
  .Recordset.Fields("Rabatt") = dRabatt
End If
 
.....