macbook上firefox可以上网，但是safari无法上网。每次用safari打开一个网站，都会
出现下面一段话：
“Comcast recommends that you take a few minutes to change your Internet
browser settings. Your browser is currently configured to use a Comcast
proxy server that is part of the process for setting up your service.
Because your service is now established, changing this browser setting will
help ensure the best online customer experience.”
但我确定我没有用代理。最近刚搬了家，换了router之类的。刚开始几天没有问题，但
用了几天后，就出现上面safari无法上网的问题，有谁知道该怎么解决的吗？xieixe！
