It is not possible to 'remove' a user if the user is responsible for content on the site because Confluence will need the user information to maintain a history of pages. If you wish to prevent a user from accessing Confluence, you can 'deactivate' a user the that they can no longer log in to Confluence.
You can however, 'remove' a user if the user has not added or edited any content on the site.
To deactivate or remove a user,
- Go to the 'Administration Console' and click on 'Manage Users' in the left panel.
All members of the Confluence-Users group are listed in alphabetical order (first name). To find a user, you can either browse through the pages, or do a search on the user's mail id or the group to which they belong.
- Click on the user link. This will display the user's current details and links to edit them.
- Click 'Deactivate' if the user is responsible for any content on the site. Deactivating will prevent them from logging in to the site. (Only prior to 2.1, see below.)
- Click 'Remove' if the user is not responsible for any content on the site.
Screenshot: Adding and removing users

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