You must have a server where email works. Or use mailcatcher solution. In admin, turn on the 'notifyloginfailures' option, setting it to send email to yourself. Using another browser, or after logging out, attempt to log in 10 times in a row using an incorrect username (one that does not match a Moodle user, for example 'frogfrog') Wait for the 'Send failed login notifications' scheduled task to run, or run it from the web (@ admin/tool/task/scheduledtasks.php) or cli (with php admin/tool/task/cli/schedule_task.php --execute='\core\task\send_failed_login_notifications_task' ) - if you run it, be aware it has an annoying limit so it won't check more than once per hour. It should show a message like 'Emailing admins about 12 failed login attempts'. The email should correctly list the fake username you used for each request, like this: 'Wednesday, 1 May 2019, 12:08 PM, IP: x.x.x.x, User: frogfrog, User full name: Unknown user' If this fix failed, there might be a fatal error running the task, or it would not include the username.