Sub CompteSansDoublon()
Dim v, tablo, d As Object, i&
v = "NOK" 'à adapter
tablo = Range("A6:C" & Range("a" & Rows.Count).End(xlUp).Row)
Set d = CreateObject("Scripting.Dictionary")
For i = 1 To UBound(tablo)
If tablo(i, 3) = v Then d(tablo(i, 1)) = ""
Next
[A3] = d.Count
End Sub