Enable WordPress Debug

Find the file wp-config.php It is usually located in the main WordPress folder. You can find it using a FTP client, or your Web Hosting Admin Panel.

Open the file and find this code:

define('WP_DEBUG', false);

Replace it with

define('WP_DEBUG', true);

Then, save the file.

This code will force WordPress to print any PHP error.

It can be useful for developers to understand what is the problem, if there's one.