Sub testx()
Dim result(1 To 3), F&, Rng, Lig&, NbLimite
NbLimite = Array(3, 6, 8)
For F = 1 To 3
'result(F) = Sheets(F).Name
For Lig = 2 To NbLimite(F - 1)
Set Rng = Sheets(F).Cells(Lig, "G").Resize(, NbLimite(F - 1))
Rng.Interior.Color = RGB(255, 255, 255) ' Fond blanc
If Not Sheets(F).Cells(Lig, "O").Value Then
Rng.Interior.Color = RGB(255, 0, 0) 'Si erreur, fond rouge
result(F) = Sheets(F).Name
err = True
End If
Next Lig
Next F
If err = True Then MsgBox "les sheets a revoir sont : " & vbCrLf & Replace(Application.Trim(Join(result, " ")), " ", vbCrLf)
End Sub