The Default Admin User

After a default installation, there is exactly one user who has access to all workspaces and functions in CORE Administration, although he is not shown as user in the Security tab settings: the admin user.

The admin user also has access to back end scripts and applications.

So he has more rights than any user that you create in CORE Administration and that you assign the Administrator role.

Depending on company security policies, you may want to keep this admin user, restrict his rights or not allow this user at all.