Bonjour,
je suppose que tu as mis une instruction option explicit, indiquant que toutes les variables utilisées doivent être définies au moyen d'une instruction Dim.
Voici donc la correction
Sub fillaex()
Dim ws1, ws2, dl1, dl2, i, re
Set ws1 = Worksheets("Feuil1")
Set ws2 = Worksheets("Feuil2")
dl1 = ws1.Range("a" & Rows.Count).End(xlUp).Row
dl2 = ws2.Range("a" & Rows.Count).End(xlUp).Row
For i = 2 To dl1
Set re = ws2.Range("A2:A" & dl2).Find(ws1.Cells(i, 1) & "/", lookat:=xlPart)
If Not re Is Nothing Then
if left(re,instr(re,"/")-1)=ws1.cells(i,1) then ws1.Cells(i, 2) = re.Offset(0, 8)
End If
Next i
Set ws1 = Nothing
Set ws2 = Nothing
End Sub