The following are the properties for tracking the progress of a message through time:
PR_CLIENT_SUBMIT_TIME
PR_CREATION_TIME
PR_DEFERRED_DELIVERY_TIME
PR_DELIVER_TIME
PR_EXPIRY_TIME
PR_LAST_MODIFICATION_TIME
PR_LATEST_DELIVERY_TIME
PR_MESSAGE_DELIVERY_TIME
PR_ORIGINAL_DELIVERY_TIME
PR_ORIGINAL_SUBMIT_TIME
PR_PROVIDER_SUBMIT_TIME
PR_RECEIPT_TIME
PR_REPLY_TIME
PR_REPORT_TIME
For more information on time properties on messages, see Message and Recipient Options.