Option Explicit
Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim Dl1 As Long ' dernière ligne
If Target.Count > 1 Then Exit Sub ' une seule colonne
If Target.Column < 17 Then Exit Sub 'colonnes pas pris en compte
If Target.Column > 22 Then Exit Sub
With Sheets(ActiveSheet.Name)
Dl1 = .Range("A" & .Rows.Count).End(xlUp).Row ' dernière ligne
If Not Intersect(Target, Range("r10:u" & Dl1)) Is Nothing Then ' zone ou on doit mettre une date
If Target = "" Then Target = Format(Now, "dd/mm/yyyy")
End If
End With
End Sub