Returns a Date indicating the date and time on which the mail message, meeting item, or post was sent. This property corresponds to the MAPI property PR_CLIENT_SUBMIT_TIME. When you send a meeting request item using the object's Send method, the transport provider sets the ReceivedTime and SentOn properties for you. Read-only.
expression.SentOn
expression Required. An expression that returns a MailItem, MeetingItem or PostItem object.