"Send Time" time stamp information is incorrect when you send a delayed delivery message in Outlook

When you use Microsoft Outlook to send a delayed message, the actual "Sent Time" time stamp information for that message is the compose time of the message and not the actual sent time. This is by design. 

In the properties of a new email message, you can use the Do not deliver before option to delay the delivery of a new message. This delay period can range from a minutes to several weeks. When the message is eventually delivered, the recipient still sees the time at which the message was composed by the client, and not the time the message actually left the Outbox. 

When Outlook is connected in Online mode to an Exchange Server mailbox, the messages are directly submitted to the Exchange mailbox. Therefore, the "Sent Time" time stamp information for that message is the time that the message was submitted to the mailbox on Exchange, not the actual time that it was delivered to the recipient.
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