Convalida Con esclusione

{=SE.ERRORE(INDICE($H$2:$H$17;PICCOLO(SE(CONTA.SE($A$2:$A$16;$H$2:$H$17)=0;RIF.RIGA($H$2:$H$17)-RIF.RIGA($H$2)+1);RIGHE($E$2:E2)));"")}

Sub ConvEscl()
Dim r, c, x, d, T

For x = 2 To Cells(Rows.Count, 8).End(xlUp).Row
    If Cells(x, 9) < 3 Then T = T & Cells(x, 8) & ","
Next x
Range("D2:D17").Select
    With Selection.Validation
        .Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:=T
        .IgnoreBlank = True
        .InCellDropdown = True
        .ShowInput = True
        .ShowError = True
    End With
Cells(1, 1).Select
End Sub