[Evolution] error storing folder 'folder'

[Carpet Nailz <carpetnailz researchintegration org>]

Is there a bottom line to this problem? I just spent a half hr reading
various reports about this problem (seems to go back many years) and all
I see are work-arounds. Did I miss a solution or is there none? Is it
just a Ubuntu problem?

I switched to Ubuntu 10.04, which provides Evolution 2.28.3, about a
month ago. Started getting the "Error storing folder 'Inbox'" message
(other people seem to get more complex messages). I tried what was
suggested in an earlier thread:

   evolution --force-shutdown
   rm ~/.evolution/mail/local/folders.db

This seemed to clear up the 'Inbox' problem, but now I'm getting the
same problem with a different folder ("Error storing folder 'Lynn'").
Now I also just go "Error while Expunging folder" after trying to empty
trash.

Did I miss a solution in my Googline, or is there none, even after all
these years? Is it just a Ubuntu problem?

Thanks