Est que il y 'a possibilité qu'ils ne soient pas dans le même dossier.
chemin = ThisWorkbook.Path & "\"
chemin = "L:\" 'à adapter
Private Sub Worksheet_Change(ByVal Target As Range)
Dim chemin$, dossier, ext$, r As Range, dos, t$
chemin = ThisWorkbook.Path & "\" '"L:\" 'à adapter
dossier = Array("", "Dossier1\", "Dossier2\", "Dossier3\")
ext = ".pdf" 'à adapter
Set r = Intersect(Target, Me.UsedRange)
On Error Resume Next
For Each r In r 'si entrées/effacements multiples
r.Hyperlinks(1).Delete
For Each dos In dossier
t = chemin & dos & r & ext
If Dir(t) <> "" Then Me.Hyperlinks.Add r, t: Exit For
Next dos
Next r
End Sub