I recently came across this error “Your PHP installation appears to be missing the MySQL extension which is required by WordPress.” on my cPanel VPS server after changing its PHP version, The error was pretty self explanatory as it was saying that MySQL extension was missing for selected PHP version. To troubleshoot this issue I have followed below steps
Find out PHP version of the site
You can find the PHP version of your site from the cPanel or WHM using the option Multi PHP manager.
On WHM you can navigate to the option called Home »Software »MultiPHP Manager and there you can find the selected PHP version for your domain.
PHP version of the site was set to PHP 7.1 and now we want to check if MySQL extension is installed for that PHP version or not.
Check if MySQL extension is installed for PHP in EasyApache 4
From your server WHM panel go to option HomeHome »Software »EasyApache 4 there you can click on customize profile to check installed components
Click on PHP extension and search for MySQL to see if it installed or not
In our case it was not installed because of which we were getting the error “Your PHP installation appears to be missing the MySQL extension which is required by WordPress” I have now selected that extension to install it on the server
Click next in easyapache and click on provision to provision that profile. Let the provision process to complete
Once the provision process is complete your error will be gone.