ERROR

hello guys, After patch 6.2 I started receiving a message saying "There was an error processing a message from the server; this may be caused by a number of issues so it is recommended that you restart your client. If it continues to occur please visit support.leagueoflegends.com with a description of the error and what you were doing at the time". I didnt bother doing anything but after the champ select my screen went all black i couldn't restart it cause it wont let me. I restarted my computer, repaired the client and reinstalled it but no one of those helped. does anyone know what to do?????????