MySQL : mysqlnd cannot connect to MySQL 4.1+ using the old insecure authentication

When trying to connect to a MySQL 4.x and later server, the following error occur :

DB connection error: mysqlnd cannot connect to MySQL 4.1+ using the old insecure authentication. Please use an administration tool to reset your password with the command SET PASSWORD = PASSWORD(‘your_existing_password’). This will store a new, and more secure, hash value in mysql.user.

This is because the MySQL Server is accepting the old style authentication for MySQL 3.x. You need to disable this by comment or remove the following parameter in “my.cnf” :

old_passwords=1