As part of your ArcTitan setup, a journaling rule must be created on your email server to allow email to automatically archive to ArcTitan.
To create a journaling rule, you need to know your journaling email address. The journaling email address has a common syntax using your company tag and your ArcTitan server name. For example, if you log onto https://archive-eu.titanhq.com/titan/company_tag, your journaling email address is firstname.lastname@example.org.
See ArcTitan Servers.