niente va in loop infinito

codice:
Private Sub trwCategorie_OLEDragOver(Data As MSComctlLib.DataObject, Effect As Long, Button As Integer, Shift As Integer, x As Single, y As Single, State As Integer)
  trwCategorie.SelectedItem = trwCategorie.HitTest(x, y)
  DoEvents
  Do Until trwCategorie Is Nothing
  Loop
  trwCategorie.SelectedItem.Expanded = True
End Sub