Sub a()
Dim i As Long
Dim strPath As String
'ici mettre le chemin du dossier contenant les gif
strPath = "C:\TEMP\"
For i = 2 To Cells(Rows.Count, 1).End(xlUp).Row
If Dir(strPath & Cells(i, 1).Text & ".gif") <> "" Then
ActiveSheet.Hyperlinks.Add Anchor:=Cells(i, 1), Address:=strPath & Cells(i, 1).Text & ".gif", TextToDisplay:=Cells(i, 1)
Else
Cells(i, 1).Font.Bold = True
Cells(i, 1).Interior.Color = 255
End If
Next
End Sub