Deleting (Archiving) User accounts
In Follow-up Users and permissions page, the accounts cannot be archived, the checkbox is only for displaying who is, or isn't archived. By checking the "include Non Active" box, you can see who is archived, but cannot add from this page.
To archive a user, you must go into the user account, but double-clicking on the email address box.
Inside the Users and Permission page is where you will De-Activate their account.
Click Exit when completed.