android中The connection to adb is down，问题和解决

自己总结的在android中常会出现的不好解决的问题和方法 
 
1.报错： 
BUILD FAILED 
D:\workspace\ganji\build.xml:144: The following error occurred while executing this line: 
D:\workspace\ganji\build.xml:271: Unable to delete file D:\workspace\ganji\tmp\proguard\tmp.jar 
解决： 
已经开了一个模拟器了，无法重新编译，必须关闭一个。用于ant 


2.报错： 
The connection to adb is down, and a severe error has occured. 
这个问题谁能解决啊 
解决： 
cmd跳到sdk tools文件路径下 
adb kill-server 
然后再adb start-server 

3.报错： 
The connection to adb is down, and a severe error has occured. 
[2010-03-11 09:36:56 - HelloOPone] You must restart adb and Eclipse. 
[2010-03-11 09:36:56 - HelloOPone] Please ensure that adb is correctly located at 'D:\OPhoneSDK_1.5 \platform-tools\adb.exe' and can be executed. 
解决： 
方法1.cmd中adb kill-server，然后adb -startserver 
方法2.方法1不管用，那么在任务管理器中杀死adb.exe，然后重启Eclipse。 
方法3.方法1和2都不管用，那么查看最后一句报错中：platform-tools中是否有adb.exe（我的错误就是在相关路径下面没有platform-tools文件夹 ，所以我选择新建一个文件夹，并且把tools中的文件全部复制到platform-tools中）