Unsuccessful log into client on imac 27 inch

9 times out of 10 when logging into game client from my imac its unsucessfull. It usually sits on "logging on" for about 5 minutes then error messeges saying I cannot connect. Internets fine, firewall is fine I just have trouble logging. Plus sometimes getting into games it doesn't connect as well. Only fix can sometimes be restarting whole computer or just getting lucky with the login. -Long time player, first time issue.