[1.7.10]ServerConnectionFromClientEvent problem

Hello there,

I want to send a packet from the server to the connected client, but i get an error rather than an arrived packet.

Not crash, just an error.

This is my code:

@SubscribeEvent
public void PlayerLoggedIn(ServerConnectionFromClientEvent event){
EntityPlayerMP player = ((NetHandlerPlayServer)event.handler).playerEntity;
if(player != null)
	AmnesiaLights.snw.sendTo(new SettingsMessageHandler(), player);
}

And this is the error when i join to the server:

http://pastebin.com/bw80eTnG

Thanks for helping me!