Dim T() As Variant, L As Long, C As Long
With Worksheets("Consultation Données").Range("n5:aa" & dernlign).Cells
T = .Value
On Error Resume Next
For L = 1 To UBound(T, 1): For C = 1 To UBound(T, 2)
If Not IsEmpty(T(L, C)) Then T(L, C) = CDate(T(L, C))
Next C, L
On Error GoTo 0
.NumberFormat = "dd/mm/yyyy"
.Value2 = T: End With