jquery conflict

I am having issues with jquery conflicting with other plugins/wordpress. Is there any solution for that? on local server on same theme there is no problem when no plugins installed. In live site I am getting Uncaught ReferenceError: jQuery is not defined
at (index):423
at (index):427

line 423 to 427 is (function() {
var messages = jQuery(‘#wce2902781edcaf413dcba1ba04c8eaa4b .wcMessages’);
if (messages.length > 0 && ‘ascending’ == ‘ascending’) {
messages.scrollTop(messages[0].scrollHeight);
}
})();