SOLVED! Error after WordPress 4.5 upgrade “Warning: mysql_connect(): Headers and client library minor version mismatch”
Solution Recommended by WordPress: Update PHP version. Steps: 1. Login to cPanel. 2. Click on PHP version or PHP Selector. 3. Select and Set the latest version of PHP (like PHP 5.5, PHP 5.6 or latest). “Solved”. For more information, https://wordpress.org/support/topic/wp45-upgrade-mysql_connect-error Author: Rajiv Sharma, Founder & CEO at mechscinovate