Try this Microsoft fix:
http://support.microsoft.com/default.aspx/kb/941090
"Messages may be stuck in the Outbox when you use Windows Mail on a
computer that is running Windows Vista"
That page offers two download options. Unless you know for sure
you have 64-bit Vista, use the 32-bit option.
Although only 'Outbox' is mentioned, it will enable removal of stuck
emails from any folder.
--
Gary VanderMolen [MS-MVP WLM]
"DAJ" <> wrote in message news:1C782FA7-38EC-4406-AE14-...
> Although configured to elimate the files when I sign out of Windows Mail,
> some files do not get eliminated.
> When I try to eliminate them manually, it reports an error and the messages
> themselves are unable to be shown.
> --
> DAJ_SANFE