Ldap_connect() / ldap_bind() not working

<?php  $ldapcon = ldap_connect("10.5.24.118")     or die("Could not connect to LDAP server.");  if ($ldapcon) {      // binding anonymously     $ldapbind = ldap_bind($ldapcon);      if ($ldapbind) {         echo "LDAP bind anonymous successful...";     } else {         echo "LDAP bind anonymous failed...";     } }  ?>

 ldap_set_option($ldapconn, LDAP_OPT_PROTOCOL_VERSION, 3);