ubuntu 14.04.1 LTS 64bit
安装完GuestAdditions后，在终端输入
sudo mount -t vboxsf sharename /mnt/share
提示错误：
mount: wrong fs type, bad option, bad superblock on sharename,
missing codepage or helper program, or other error
(for several filesystems (e.g. nfs, cifs) you might
need a /sbin/mount.<type> helper program)
In some cases useful info is found in syslog - try
dmesg | tail or so
ll /sbin/mount.vboxsf
看到 mount.vboxsf 是一个符号链接，是红色
sudo find / -name mount.vboxsf
在下面位置找到
/opt/VBoxGuestAdditions-4.3.10/lib/VBoxGuestAdditions/mount.vboxsf*
在/sbin/ 下面重新建立符号链接，再次mount，成功
virtualbox sharefolder mount fail
原文：http://www.cnblogs.com/elodio/p/virtualbox_sharefolder_mount_fail.html