选择一个hosts文件，然后按照不同操作系统执行下面的命令授权：

Windows Vista/7
To Users group cacls %windir%/system32/drivers/etc/hosts /E /G Users:W

Custom User account cacls %windir%/system32/drivers/etc/hosts /E /G "User Account Name":W

Linux (Ubuntu Fedora ...)
sudo chmod og+w /etc/hosts

Mac OS X
sudo chmod og+w /etc/hosts