Private Sub chercher(chaine As String)
Dim j As Byte, i As Byte, Message As String
Dim t(), cell1 As Range, cell2 As Range
ReDim t(1 To Workbooks.Count)
For j = 1 To UBound(t)
t(j) = Workbooks(j).Name
Next
Set cell1 = Workbooks(t(1)).Sheets(1).Cells.Find(What:=chaine, after:=Cells(1, 1), MatchCase:=False)
Set cell2 = Workbooks(t(2)).Sheets(1).Cells.Find(What:=chaine, after:=Cells(1, 1), MatchCase:=False)
Titre = "valeur cherchée: " & chaine & vbCrLf
Message = "Trouvée dans :" & vbCrLf
Message = Message & t(1) & ": " & cell1.Address(0, 0) & vbCrLf
Message = Message & t(2) & ": " & cell2.Address(0, 0) & vbCrLf
MsgBox Message, vbInformation, Titre
End Sub