adb :unknown host service

 adb 没法重启
   现象：C:UsersJohn>adb shell
             adb server is out of date.  killing...
            ADB server didn't ACK
            * failed to start daemon *
            error: unknown host service
   分析：主要是由于5037端口被占用，android_sdk中的adb无法启动
   解决： 在console中输入 netstat -aon|findstr "5037" 查看占用的pid

2.   协议    本地地址              外部地址                状态           PID  
3.  TCP    127.0.0.1:5037       0.0.0.0             LISTENING       2244

               输入tasklist /fi "pid eq  2244             
               taskkill /pid 2244  /f          kill掉该进程
               重启adb