I don't know if you guys can remember about me, and even if this forum still alive (i hope it is).
Anyway, I am here to warn you about that GameSpy is about to shutting down its services, this mean that Halo, like many others games, will no longer have a server list.
More infos here: http://www.343industries.org/forum/topic/34236-halo-combat-evolved-muliplayer-servers-shutting-down/
(you can find further infos on the net).
For this reason the Halo community started a petition trying to get a new Master server on Steam, to keep Halo alive(including Halo CE ofc), if you want help to keep up this amazing game, you can put your signature here PLEASE: https://www.change.org/petitions/steam-adopt-halo-combat-evolved-custom-edition-multiplayer#
Thanks for yours Attention!