Hydruid,
They are in two different areas: (1) under "infrastructure" --> "devices" --> "discovered(8)", the main window doesn't display any device (no filter ). The discovery said 8 devices, btw they did report in the events because they are not belong to any class yet; (2)The second area is "http:<localhost>8080/zport/dmd/manage" url, where those 8 discovered devices are listed in devices(expanded) under the contents tag, and I can mark it to delete, but zenoss will pop-up an error window after delete action.
Sorry to confuse you, I can't attach any screenshots from work...