PHP - Warning: ldap_bind(): Unable to bind to server: Invalid credentials

<?

$host      = "ldap://adds-01.aldeasinfantiles.local";

$puerto   = 389;

$conex = ldap_connect($host,$puerto) or die ("No ha sido posible conectarse al servidor");

echo "<br>conexion: ".$conex;

$admin="#####r";

$passwd=#####'; 

if (ldap_set_option($conex, LDAP_OPT_PROTOCOL_VERSION, 3)) {

    echo "<br>Using LDAPv3";

} else {

   echo "<br>Failed to set protocol version to 3";

}

if ($conex) {

   // bind with appropriate dn to give update access 

   $r=ldap_bind($conex, $admin, $passwd);

   if ($r)

       {echo "<br>Congratulations! $admin is authenticated.";}

   else

       {echo "<br>Nice try, kid. Better luck next time!";}

   ldap_close($conex);

} else {

   echo "<br>Unable to connect to LDAP server";

}