Sub essai_date()
Dim DateCherche
Dim CelluleTrouve As Range
DateCherche = Format(ActiveSheet.Range("G4").Value, "dddd d mmmm yyyy")
Set CelluleTrouve = Sheets("attachement").Range("K1:N1").Find(DateCherche, , xlValues, xlWhole)
If Not CelluleTrouve Is Nothing Then
Sheets("attachement").Select
CelluleTrouve.Select
Else
MsgBox "Date non trouvée"
End If
End Sub