php error: The Encrypt library requires the Mcrypt extension in codeigniter

Question

I have a login and sign up form and use the encrypt library to encrypt the password.. I am using Xampp for my server and my system works correctly..

code to encrypt the password:

$this->encrypt->encode('my password'); 

add encrypt library

 $autoload['libraries'] = array('encrypt');

and setting the secret key in config:

$config['encryption_key'] = 'nmsc encrypt secret key';

My code works well using xampp server in windows but when Im trying to upload my website to ubuntu server I've got an error says

The Encrypt library requires the Mcrypt extension

how to fix that problem? refering this guide https://www.codeigniter.com/user_guide/libraries/encryption.html but I dont know how to install that mcrypt. my website needs to run from ubuntu server. how to install or fix that problem?

Answer 1

Best solution is (only available for CI 3 and up):

change

 $this->load->library('encrypt');

to

 $this->load->library('encryption');