Macro pour insérer un mot (prédéfini) en début de texte, sur une colonne...

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
If Target.Column <> 2 Then Exit Sub
If Target.HasFormula Then Exit Sub
Cancel = True
If Left(Target, 7) = "RUPTURE" Then
    Target.Value = Mid(Target.Value, 9)
Else
    Target.Value = "RUPTURE " & Target.Value
End If
End Sub

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
        If Target.HasFormula _
            Or Target.Column <> 2 _
            Or Target.Count > 1 Then ' par sécurité... car en double click une seule cellule 
                Cancel = True
                Exit Sub
        End If
        If UCase(Left(Target, 8)) = "RUPTURE " Then
                Target = Mid(Target, 9, 9 ^ 9)
                Target.Font.Color = vbBlack
        Else
                Target = "RUPTURE " & Target
                Target.Characters(1, 8).Font.Color = vbRed
        End If
End Sub