DISCLAIMER: The feature is supported in X-Cart 5.4.x and earlier.
A root store administrator and an administrator with user management permissions can force users to log out of their accounts. You can do this for every user account except anonymous customers.
To to log out a user:
In the store's user list (Users > Users List), open a user account for viewing/editing.
On the Account Details page, select the "Logout this user" option in the "Profile actions" drop-down.
The system will log out the user and show you a report.