/opt insufficient permissions [duplicate]
Solution 1:
Well, try the following:
Reboot into single user mode, this is archieved by holding down alt(option) + s while rebooting.
At the prompt /sbin/fsck -fy(careful, QWERTZ-Layout), after that type /sbin/mount -wu. Now /bin/chmod 1775 /. At last /bin/sync,then exit.
This will check your filesystem integrity and correct permissions for your root directory.