You can trace mail in the Secure mail flow console as follows
Login to the Console
Select the Mail Tracking option from the Logs tab.
In the left pane, select the time range for the search. Even though the system maintains logs for the last 30 days, you can query for only 7 continuous days or less in a single query.
Select the Direction of the mail flow, Sender, Recipients and/or Subject.
The search results are visible in the right pane and are classfied as Blocked Traffic, Accepted Traffic and Unresolved Traffic.
Blocked Traffic will show all the attempts to send mail from sources who were blocked by the IP reputation based filtering checks.
The Accepted traffic includes mail which were accepted for processing and can be quarantined as spam or delivered to the mail server.
The Unresolved Traffic tab shows mail that cannot be uniquely identified.