As per this post:
However, due to technical difficulties which occurred just before the start of the emergency maintenance, certain players in the Aether and Chaos data centre Worlds continue to be unable to log in.
There is a malfunction of the database server equipment, which we are currently continuing to work on, and we ask for your patience. For details on this technical difficulty, please refer to the news post “North American/European Data Centre Several Worlds Technical Difficulties (Jul. 23): Follow up”.
We apologise for any inconvenience this may cause and thank you for your understanding.