This isn't a bug. All of us at some point has experienced this message. The only way through this is to keep trying until you are able to open the client. I find that only having mapleroyals opened helps.
Don't worry boys I found a fix. Instead of opening one at a time, I spam open them so I open about 10 at a time, 1 out of the 10 should work. It's like playing Baccarat, if you bet tie hand the odds for the cards being a tie is like every 8 hands.
Update: ok the error is on steroids now, my cheap trick won't even work anymore. So along with the first error shown, I get another one, look There's another one similar to this too, -numbers (Unspecified error) so 3 errors altogether and the fourth error doesn't even pop up just double click royals, app launches, app closes straight away. I've tried restarting, opening without any other apps as that guy said, doesn't help at all. What's going on? Also, this almost never happened before, very rarely but since 1 or 2 updates ago, it happens every time.