WPML: Getting automatic updates while blocking external HTTP requests

Due to security reasons I’m blocking external HTTP requests on many of my sites through a setting in wp-config.php. See this article for further exploration on working security through wp-config.php. Here’s the setting:

define( 'WP_HTTP_BLOCK_EXTERNAL', true );

This measure prevents a couple of plugins – mainly premium plugins that are not available through the offical WordPress plugin repository – from fetching their updates.

This was the case as well for the popular WPML multi-language plugin.

The fix is easy – by allowing WordPress to call only certain servers. In this case it is the server d2salfytceyqoe.cloudfront.net – as detailed here in the WPML support forums. This is how it looks in the wp-config.php:

define( 'WP_ACCESSIBLE_HOSTS', 'd2salfytceyqoe.cloudfront.net' );

You probably want to add more servers here, like *.wordpress.org et al.

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UPDATE NOV. 25, 2017:

In order to reveive updates for the popular Toolset plugin suite by the makers of WPML you need to whitelist the following two servers, according to their support:

define( 'WP_ACCESSIBLE_HOSTS', 'api.wp-types.com, d7j863fr5jhrr.cloudfront.net' );