I found that sending large attachments (> 2Mb) with an email results in Outlook leaving the message in Outbox while it continues to send multiple copies. I've seen it send over ten copies to the addressee. But it never gets cleared and there is not a copy in the Sent folder. Reported to my ISP, who instructs me to "increase connection time in Outlook", but does not tell me how.
Agree that this is the problem? If so, I cannot find the right spot on the menu of O 2003 to set this.