Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim Derlgn as integer
Cancel = True
With ActiveSheet
Derlgn = .Cells(.Rows.Count, 6).End(xlUp).Row 'On Détermine la dernière Ligne Non vide de la Colonne "F" "Participants"
If Not Intersect(Target, .Range(.Cells(3, 5), .Cells(derlgn, 5))) Is Nothing Then 'Si Targer dans la Bonne Plage
Target.Value = IIf(Target.Value = Empty, "x", "") 'On met ou Enlève le "x" de la cellule
End If
End With
End Sub