启动Apache出现错误Port 80 in use by "Unable to open process" with PID 4!

22:15:30  [Apache] ?Problem detected!
22:15:30  [Apache] Port 80 in use by "Unable to open process" with PID 4!
22:15:30  [Apache] Apache WILL NOT start without the configured ports free!
22:15:30  [Apache] You need to uninstall/disable/reconfigure the blocking application
22:15:30  [Apache] or reconfigure Apache and the Control Panel to listen on a different port

错误提示：是由于系统的服务占用了80端口，要么结束系统服务，要么修改apache端口。

PID4的服务是World Wide Web Publishing Service

这里选择结束这个系统服务，运行services.msc，找到然后停止即可。防止下次开机再出现这种情况，在属性里可设置成手动启动。