Message `unexists'

[Harry Putnam <reader@newsguy.com>]

I've seen the unlikely statement `message unexists' turn up in these
circumstances:

In agent mode  Select an undownloaded message and put the download
(%) mark on it.  Close group go plugged and press `J u' on that group.
To down load the wanted message.

Go unplugged again and open group, then try to open the message in
question.

That `unexists' message pops up.   I've found if I open a different
message then come back to the newly downloaded one, something is
cleared somewhere and the message opens.

This time I have a particularly stubborn case where the above proceedure
still won't open the message, and I continue to get the `unexits' message.

Repeated attempts at marking for download, downloading with `J u'
opening various messages then the questionable one, and I still get:

`Message unexists'   What does that unlikely statement really mean anyway.