Bonjour,
Pour convertir en dates :
Sub ConvertirDates()
Dim c As Range, n%
With ActiveSheet
n = .Range("A" & .Rows.Count).End(xlUp).Row
For Each c In .Range("A2:A" & n)
c = DateSerial(c Mod 10000, (c \ 10000) Mod 100, c \ 1000000)
Next c
End With
End Sub
Cordialement.