On the low level, you would need to change the value of the
PR_CLIENT_SUBMIT_TIME MAPI property using CDO 1.21/ Redemption / Extended
MAPI.
On the Outlook Object Model level, MailItem.SentOn propety is read-only.

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool
-
"Richard Brice" <richard.brice@vega.co.uk> wrote in message
news:e2M8MU7zIHA.1236@TK2MSFTNGP02.phx.gbl...
> We develop simulation environments for training and serious-gaming.
>
> In a current simulator, we intend on using Outlook and Exchnage for
> electronic messaging but have an issue with the sent timestamp. There is
> the real time and the mission time (i.e. the time the training session is
> running at). Mission time and real time are not the same.
>
> We would like the sent field to be timestamped with the mission time. We
> can create a dll or service that provides a alternative clock source for
> the mission time, naturally the real time would be provided by the system
> clcok.
>
> How can Outlook be configured to use an alternate time source, in this
> case the mission time?
>
> What is the format of the time and the interface mechanisms of the
> alternative clock?
16 Junchange sent timestamp in Outlook.Richard Brice
16 Jun\ Re: change sent timestamp in Outlook.Dmitry Streblechenko
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