PHP Mail function should be installed on your server if you want to send emails from your code, to install

1. Install Pear package (if it is not already installed) by running

Debian/Ubuntu:

apt-get install php-pear

Redhat/CentOS:

yum install php-pear

2. Once the pear installation is complete or if you have PEAR already installed, you can go ahead and install PHP mail and its dependencies function by running

pear install mail
pear install Net_SMTP
pear install Auth_SASL
pear install mail_mime

3. Once done, you can restart the webservice on the service using

Debian/Ubuntu:

service apache2 restart

Redhat/CentOS:

service httpd restart

That’s it, PHP Mail function is successfully installed on your server.

You can test the function by using the test SMTP Scripts.