If you wish to use the WordPress JetPack plugin on your WP website you must verify your WordPress.com account before any of the JetPack features are enabled and usable.
To verify your WordPress.com account, JetPack uses the WordPress xmlrpc.php file located at yourdomain.com/xmlrpc.php.
When you attempt verification you might encounter the following error:
Warning: ini_set() has been disabled for security reasons in …/load.php on line 278.
This error shows up because your webhost has disabled the use of ini_set php function globally.
There are a number of ways you can reenable the ini_set function.
If you have access to your server’s php.ini file, open it and search for the following lines:
; This directive allows you to disable certain functions ; for security reasons. It receives a comma-delimited list ; of function names. This directive is *NOT* affected by ; whether Safe Mode is turned On or Off. ; http://php.net/disable-functions disable_functions = show_source, system, passthru, exec, popen, proc_open, allow_url_fopen, ini_set
If you find that that ini_set is listed as one of the disabled functions, remove it.
If you have access to your php configuration via cPanel, you can edit configuration values by navigating to cPanel’s PHP Configuration section. Once there, switch to Advanced mode and modify the disable_functions field.
If you control your server and your server is managed using the Web Host Manager (WHM), in the left sidebar of WHM search for and click on Service Configuration. Under Service Configuration select PHP Configuration Editor. Once there, switch to Advanced mode and edit the appropriate field.
You will find that a number of webhosts say they have disabled ini_set for security reasons, but the more likely argument is they have done it to prevent resource hogging. Use of ini_set from within php code allows for modification of global php configuration settings including how much memory a script uses and for what length of time the script uses that memory at any given time.
Most popular CMSs including WordPress, Joomla and Drupal rely on ini_set to function properly so you will most probably have to enable this setting to make full use of them.