Bizarre, bizarre...
Remplacez le code par celui-ci :
Private Sub Worksheet_BeforeRightClick(ByVal Target As Range, Cancel As Boolean)
Dim I As Integer, Colonne As Long, DerniereLigne As Long, PositionVirgule As Integer
Dim TabCellules As Variant
Dim Coordonnee1 As String, Coordonnee2 As String
Coordonnee1 = "": Coordonnee2 = ""
If Selection.Count = 2 Then
TabCellules = Selection.Address
For I = 1 To Len(TabCellules)
If Mid(TabCellules, I, 1) <> "," Then
Coordonnee1 = Coordonnee1 & Mid(TabCellules, I, 1)
Else
PositionVirgule = I
Exit For
End If
Next I
For I = PositionVirgule + 1 To Len(TabCellules)
Coordonnee2 = Coordonnee2 & Mid(TabCellules, I, 1)
Next I
If Range(Coordonnee1).Column = Range(Coordonnee2).Column Then
Colonne = Range(Coordonnee1).Column
DerniereLigne = Cells(Rows.Count, Colonne).End(xlUp).Row + 1
Cells(DerniereLigne, Colonne) = Range(Coordonnee1) & " " & Range(Coordonnee2)
End If
End If
Cancel = True
End Sub