MapleEurope just announced that they are currently in the development stages of making EMS compatible with the latest Windows operating system, Windows 8.1.
We are always working hard to bring you the latest compatibility updates to ensure
that MapleStory Europe works flawlessly with all Windows Operating Systems.
Currently in development are fixes to ensure that Windows 8.1 will provide just as good performance as previous versions.
However, please note that MapleStory Europe is not officially compatible with any RTM versions of Windows 8.1.
Because of this, please carefully consider your decision to install these as game performance may be affected.
We will inform you in the near future about official support for Windows 8.1 and how it will impact gameplay.
MapleStory Europe Team