How exciting when you get a new request for access to your TNG site by a new user. Perhaps it is someone very new to you. Perhaps it is someone emailing you from firstname.lastname@example.org, that is, has a country code of Russia, and has an address allegedly in Thailand. So, not likely this is a serious researcher of your surname.
How do you make sure your TNG site has some protection from such intruders? You set automatic approval of new users to “No”. You will still get requests, but you get to block them from access before you review the request.
Log into your TNG site as administrator. Open the Administration panel and select Setup. Then go to General Settings.
Open the Mail and Registration section. Find “Auto approve new users:” and set it to “No”. Click the Save button.