It’s sad to hear it go, but the fabled Halo 2 Multiplayer will now only exist via LAN connections. First the service was shutdown on the Xbox 3 years ago, and now the PC version will suffer the same fate.
Wildly regarded as the most competitive friendly Halo multiplayer is now over.
To switch gears ever so slightly, we’re sad to report that the service end-date for Halo 2 PC Multiplayer will be February 15, 2013. We’ve been monitoring the population for months, and it’s been peaking consistently at approximately 20 players or less. Those that own this game can continue to enjoy Multiplayer over LAN after that date; however our network services will be turned off at that time. We love you, Halo 2 PC, and you will live forever in our hearts.
#singletear – HaloWaypoint
Adios dual wield SMGS,
– Chief Landless
Source: HaloWaypoint Bulletin