We are aware of the Nexon Game Security (NGS) errors that many players have been receiving since today’s February 1st game update. We understand that this error is causing players to disconnect from the game intermittently.
This error was caused due to a mismatch with a file provided with the game update and the current NGS version. We are currently working on a resolution for those players who have not yet updated their MapleStory client to v181.
If you have updated your MapleStory client to v181 already, please download the BlackCipher files here and follow the instructions to replace them in your client. After replacing the files and restarting your client, the NGS update error will be resolved.
If you still encounter errors after following the above steps, please send a support ticket through our Customer Support Center here.
We apologize for the inconvenience this has caused. We will provide further updates as they become available.
Thank you for your patience while we continue to look into this issue.
-The MapleStory Team