>>Memory card reader with empty slots. See screenshot.
>
>OK, I guess an empty optical drive is somehow treated differently from an empty card reader "drive".
>
>I see you've worked around the issue using the FSO. However, I *think* WMI has a lot of detailed information about storage devices. I don't know if that includes (reliable) information about the presence of media.

I'm happy with FSO - WMI promises a lot, but somehow it sounds like a too heavy piece of artillery for this mosquito of a problem.