voilà ta macro corrigée
Option Explicit
Sub calendrier()
Dim DateDepart As Date, DateMaturite As Date
Dim date1 As Variant
Dim date2 As Variant
Dim Pas As Variant
Dim Cel As Range
'date1 = "16/1/2003"
'date2 = "16/12/2003"
date1 = InputBox("Entrez la date à laquelle vous évaluez votre option ", "Date d'évaluation", Date)
date2 = InputBox("Entrez la date de maturité ", "Date de maturité", Date)
Pas = InputBox("Entrez le pas de l'option", "Pas de l'option")
DateDepart = CDate(date1)
DateMaturite = CDate(date2)
Set Cel = Range("A1")
While DateDepart < DateMaturite
DateDepart = DateAdd("d", Pas, DateDepart)
If DateMaturite - DateDepart < 100 Then Exit Sub
Cel = DateDepart
Set Cel = Cel.Offset(1, 0)
Wend
End Sub