基于 这个问题 和这个问题，我建议您检查您没有运行任何防火墙或端口阻止软件(如 PeerGaurdian)，并且您不会在系统的任何位置阻止 Amazon/EC2.

Based on this question and this question, I'd suggest you check that you don't have any firewall or port blocking software running (like PeerGaurdian) and that you're nto blocking Amazon/EC2 anywhere on your system.