问问题前先搜索ISSUE，并搞清楚下面的问题:

1. 检查 ```-key xxx``` 至少三遍, ***保证***两边一致。
2. 保证```-nocomp, -datashard, -parityshard,  -key, -crypt```两边一致。
3. 是否在服务器端，正确设定了转发的目标服务器地址 ***--target***。
4. 如果第3条不确定，尝试在服务器上telnet target port试试。
5. 防火墙是否关闭了UDP通信。
6. 两端的版本是否一致？
7. 是不是最新版本？
8. 两端分别是什么操作系统？
9. 两端的输出日志是什么？

Before firing issue, make sure you figured out the following common questions.

PLEASE DO SEARCH FIRST.

1. Check your ```-key xxx``` for at least 3 times, ***MAKE SURE*** both sides share the same secret.
2. ```-nocomp, -datashard, -parityshard,  -key, -crypt``` ***must be the same*** on both side.
3. Did you correctly set the ***-target*** on the server side?
4. ***MAKE SURE*** ```telnet target port``` on your server successful(don't ask me why couldn't).
5. Does your ***firewall allows UDP*** communications? (including your ISP Cable-Modem)
6. Are you using the **same version** for both client & server
7. Are you using the **latest release**?
8. Which **OS** do you use?
9. Which end for this issue related to, **client or server**?


