By default, WordPress automatically checks if plugins updates are available, and if yes, ask you to install it. It is useful in most cases, but when building websites for clients you may not want them to updates plugins, for example if you modified a plugin especially for them. Here is an easy way to disable plugin updates on any WordPress blog.
Nothing complicated: Simply paste the following code into your functions.php, save it, and you’re done.
remove_action( 'load-update-core.php', 'wp_update_plugins' ); add_filter( 'pre_site_transient_update_plugins', create_function( '$a', "return null;" ) );
Thanks to WP Snippets for the useful tip!