After login in on a server, I received the message (in red letters in the lower left corner of the screen) that my character couldn't be loaded, was reset and that I should contact an admin. After that I received a message in the middle of the screen, which said that I should reconnect to a server. It also included a restart button. I did reconnect to another server where I started with a fresh character. All progress was lost!
Unfortunately I can't remember the server names, but they were all German servers.