Private Sub CommandButton1_Click()
Dim i As Integer, Verif As Boolean, r As Long
With Sheets("UTILITAIRE")
r = Application.Max(3, .Range("AM" & Rows.Count).End(xlUp).Row) 'je suppose que l'entête est la ligne 3 et les données commencent à la ligne 4
For i = 4 To r
If ComboBox1 = .Cells(i, 39) Then Verif = True: Exit For
Next i
If Not Verif Then
ComboBox1.Copy
.Cells(r + 1, 39).PasteSpecial Paste:=xlPasteValues, Operation:=xlMultiply, SkipBlanks:=False, Transpose:=False
End If
End With
End Sub