By adding this code I get the first field (A) to colour yellow so I
guess I am getting close...............

Sheets("hoofdblad").Select
Range("A1").End(xlDown).Offset(1, 0).Formula = NieuwArtikelNr
If ProduktCode = "sw" Then
Range("A1:J1").End(xlDown).Offset(0, 0).Interior.ColorIndex =
6
End If

Now, how do I extend this to the whole row?

TIA Henro