From the Maple Site:
This morning, we lost power in our west coast server center which caused all servers to unexpectedly shut down. This downtime affected our website as well as game and login servers. We apologize for the downtime and our inability to update you quickly about this issue. Right now we are on emergency power at the server center and while all game servers are up we are still experiencing issues with MapleStory. For now we advise players to not log into the game. We may require some maintenance on the database before you are able to log in normally. Please continue to check back here for updates.
– MapleStory Staff -
ALL SITES AND GAMES SEEM TO BE ONLINE SO YA WE WILL UPDATE ON THE REASON WHEN WE COMPLETELY KNOW.
It seems that all the Nexon webpages have crashed, and are unreachable. This means that anyone that can only use the website method of entering the game cannot enter, and Nexon.net, and all the nexon game sites are not reachable, we don’t know what happened, and there has been no notifications on the Twitter or Facebook of Maple Story. We will update you on anything we figure out.
There are rumors that there are some new exploits surfacing, and Nexon has gotten wind of them, but that does not explain why all of the Nexon Games, and webpages are offline. 12:37 est.
This could also be a DDoS on the Nexon Sites, but that would be a very crazy thing to plan, but it can be a possibility. 12:39 est.
Another possibility for the cause of this could be a Earthquake. There are reports of a 3.2 magnitude Earth Quake in Central Cali a few hours ago, so this may have resulted in power lines, and etc being knocked out. It would explain why all the sites are offline, and the games. 12:53 pm
Seems there may have been an earth quake, and it has caused power outages, as you can see on this map http://www.sce.com/AOC_Outagemap/OutageMap.html! We will notify you when the servers are online.