fetch_feed works on localhost but not on server

At first check or set the timeout window on the online install, keyword max_execution_time.

Also a hint to the feed, there have a issue, often also a problem for the connection: http://validator.w3.org/feed/check.cgi?url=http%3A%2F%2Fparticipmontpellier.wordpress.com%2Ffeed%2F

Also a chance is a plugin or function inside the Theme, that cut the connection.

The last point, that you should check this two constants. Ther should be on true value for connections.

  • WP_HTTP_BLOCK_EXTERNAL
  • WP_ACCESSIBLE_HOSTS

More background about WordPress and Offline Topic can you find in this source of the plugin. But you must check the contrary 😉