You can revoke Out-of-the-Box's access to your Dropbox account in two places. For full revocation, do both.
1. In the plugin (WordPress)
On the plugin's settings page in your WordPress dashboard, click the deauthorize option next to the linked Dropbox account. The plugin removes the stored access token from your site.
2. In your Dropbox account
- Sign in at dropbox.com/account/connected_apps.
- Find Out-of-the-Box in the list of linked apps.
- Click the X next to the entry to unlink it.
If you're using your own custom Dropbox app, you can also delete the app at the Dropbox App Console. That removes all OAuth grants for that app at once.
What happens after revocation
The plugin loses access to the Dropbox account immediately. Re-authorize from the plugin's settings page if you want to reconnect.
For an overview of revocation across all providers, see How do I revoke the plugin's access to my cloud account?