Location: Settings link in Settings > Site administration > Plugins > Authentication > Manage authentication
This authentication method enables users to create their own accounts if email-based self-registration is selected from the self registration drop-down menu in the common settings section on the manage authentication page. They then receive an email at the address they specified in their account profile to confirm their account.
Warning: Enabling self registration results in the possibility of spammers creating accounts in order to use forum posts, blog entries etc. for spam. This risk can be minimized by limiting self registration to particular email domains with the allowed email domains setting in Settings > Site administration > Plugins> Authentication > Manage authentication. Alternatively, self registration may be enabled for a short period of time to allow users to create accounts, and then later disabled.
Note: The Email-based self-registration authentication plugin must be enabled to allow users who previously self-registered to login. Selecting Email-based self-registration as the self registration method allows potential users to self register.
Enable reCAPTCHA element
A CAPTCHA is a program that can tell whether its user is a human or a computer. CAPTCHAs are used by many websites to prevent abuse from bots, or automated programs usually written to generate spam. No computer program can read distorted text as well as humans can, so bots cannot navigate sites protected by CAPTCHAs.
Spam protection may be added to the email-based self-registration new account form with a CAPTCHA element - a challenge-response test used to determine whether the user is human.
In addition to enabling the reCAPTCHA element, email-based self-registration should be set as the self registration authentication plugin and reCAPTCHA keys should be set in the manage authentication common settings.
Using Moodle forum discussions: