Bonjour, ZAKAO
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim c As Range, liste$
For Each c In [C17:H27]
If c.Interior.Color = vbRed Then liste = liste & "," & c
Next
With [C12].Validation
.Delete
.Add xlValidateList, Formula1:=Mid(liste, 2)
End With
End Sub