• Download and install this folder as prescribed in moodle documentation.
• Login as admin.

• Click site Administration->Plugins->Authentication->Manage Authentication.

• Enable External Database Authentication.

• Then Click on settings.

• Fill the form as below.

Host as localhost.
Database as MySql.
DB Name as WordPress DataBase Name.
DB User as WordPress DataBase User Name.
Password as WordPress DataBase Password.
Table as WordPress Users table (Mostly wp_users).
User name as user_login.
Password as user_pass.
Select password format as WordPress.

• submit it by click save changes.
• Now user can login with the wordpress user name and password.