Although the Sender object is presented, it looks like it is not supported -- an email Sender is always the default address of the local email client.
Be sure that all attached files are accessible at the moment when you are invoking the MAPISendMail function.
This class does not use MAPILogon and MAPILogoff functions (hSession=0). In this case -- it is called an implicit logon -- the MAPI session is temporary. The implicit session opened for the call is closed by the time the call returns.
Tested on Windows XP Home Edition, Outlook Express 6.
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