Win32-MAPI problem

[Meursault]

I have been trying to send mail via MAPI using this little example in
*Python Programming on Win32*, but run into trouble when using the
"session.DeliverNow()" method.

Up to creating and sending the message to the MAPI server, everything
seems to go fine, and "newMsg.Send()" puts my message right in the
Outlook (2000) outbox. But running "session.DeliverNow()" to transmit
messages gives me the following:

Traceback (innermost last):
  File "<pyshell#8>", line 1, in ?
    session.DeliverNow()
  File "C:\Program
Files\Python\win32com\gen_py\3FA7DEA7-6438-101B-ACC1-00AA00423326x0x1x21.py",
line 3609, in DeliverNow
    return self._ApplyTypes_(0x6c, 1, (12, 0), (), 'DeliverNow', None)
  File "C:\Program
Files\Python\win32com\gen_py\3FA7DEA7-6438-101B-ACC1-00AA00423326x0x1x21.py",
line 2279, in _ApplyTypes_
    return self._get_good_object_(apply(self._oleobj_.InvokeTypes,
(dispid, LCID, wFlags, retType, argTypes) + args), user, resultCLSID)
com_error: (-2147467259, 'Unspecified error', (17389, 'Collaboration
Data Objects', 'An unexpected error has occurred. [MAPI 1.0 -
[E_FAIL(80004005)]]', None, 0, -2147467259), None)


This is not how it happens in the book!

Any ideas about what's going on?