How to connect to a website via LDAP in PHP?

Question

PHP

How to connect to a website via LDAP in PHP?
Not a single site can connect anonymously or by account. What am I doing wrong?
<?php
//using ldap bind anonymously
// connect to ldap server
$ldapconn = ldap_connect("dotnet46.ru")
or die("Could not connect to LDAP server.");
if ($ldapconn) {
// binding anonymously
$ldapbind = ldap_bind($ldapconn);
if ($ldapbind) {
echo "LDAP bind anonymous successful...";
} else {
echo "LDAP bind anonymous failed...";
}
}
?>