This is exactly what happened to my bro, sister-in-law, and I!
My bro played fine 3 hours ago. I just came to his house after school and tried logging in my 'LUBU' on my laptop and it says this character belongs to someone else. My bro then tried logging in from his desktop and it now tells him that his 'konvict' belongs to someone else. I then tested my brother's wife's char and it too says that her character belongs to someone else.
Halp
UPDATE: 15min later, I tried logging in my 'LUBU' on his desktop instead but now it says "Incorrect authorization key" (without being able to enter the server at all now).
UPDATEE: 5min later, I successfuly log into 'LUBU' on his desktop by NOT using the cRPG launcher.