问题描述：UUID已经存在
Cannot register the hard disk 'F:\hadoop\VirtualBox-centos\centos6.4\centos6.4.vdi' {05f096aa-67fc-4191-983d-1ed00fc6cce9}
because a hard disk 'F:\hadoop\VirtualBox-centos\centos6.4\centos6.4.vdi' with UUID {05f096aa-67fc-4191-983d-1ed00fc6cce9} already exists.
错误代码：
返回代码:E_FAIL (0x80004005)
被召者RC:VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)
解决方法：
1.打开cmd ，切换目录至virtual box的安装目录下：（我的在： F:\Program Files\Oracle\VirtualBox）
2.执行 vboxmanage 生成新的 UUID，path是对应vdi的所在位置
格式： vboxmanage internalcommands sethduuid X:\path\xxx.vdi
实例：vboxmanage internalcommands sethduuid "F:\hadoop\VirtualBox-centos\centos6.4\centos6.4.vdi"
