Well, after some hard searching I guess I've found an answer http://www.pcreview.co.uk/forums/thread-3661672.php

According to Ken Slovak - [MVP - Outlook]

"I'm not familiar with Thunderbird, and it really doesn't matter if
Thunderbird can do it, Outlook can't. You won't find that property in sent
items in Outlook. Wishing won't make it so."


Argh.



Posted as a reply to:

Obtaining the Message-ID (rfc882) from a sent mail
23-Sep-09

Hi, I'm having problems seeing the message headers of sent mails.

I have a simple outlook add-in that's showing me the message headers of emails. Currently, it works for received mails, but I can't obtain the information for sent messages.

The same thing happens when I manually go into Outlook and go to the options menu. It doesn't show any information for sent mails, while for received ones, the info is there.

Can anyone explain to me the cause of this?

Thanks.

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