An employee has recently left an organization and a manager suspects that this employee may...

An employee has recently left an organization and a manager suspects that this employee may have made changes to the system that no one is aware of. Mobile and Remote Access registration is not working. Internal communications appear to be working, but no external system is able to register or call anywhere. While investigating this problem, it is discovered that no internal systems are able to call externally either. What is the TraversalZone missing that is causing this issue?