Site went down after update

Hello,

It seems after an update I received the message below from the plugin Elite Members, I since then disabled the plugin and we are able to access the site again. However, could someone please point me into why this failed? I have tried reinstalling the plugin but that did not work.

Deprecated: Function create_function() is deprecated in /home/website/public_html/wp-content/plugins/elite-members/admin/em-widgets.php on line 168