Http Error 500 when activating Divi on WordPress that’s running PHP 7.1

1. First, we need to make sure that your server meets WordPress requirements, so please double check with your hosting if your server has:

• PHP 7 or greater
• MySQL 5.5 or greater
• The mod_rewrite Apache module
• More info: https://wordpress.org/about/requirements

2. Please, check if those PHP directives have the same values, or higher in your server configurations:

• post_max_size 128M
• memory_limit 256M
• max_execution_time 180
• upload_max_filesize 256M
• max_input_time 600
• max_input_vars 5000

3. Add the following line to the .htaccess file located in your WordPress root directory (the same directory that contains your wp-config.php):

<IfModule mod_substitute.c>
SubstituteMaxLineLength 10M
</IfModule>