That's not an error - it's telling you that you do not have permission to read the files in that directory as a normal user as you will see if you click on it.
If you want to see the contents of the directory you must do so as root. In a terminal type:
sudo -i nautilus
You notice that you have to enter your password. Now you have root privilege so you can view, edit and delete anything you want, so you should be careful because you could break your system - you shouldn't use root permission unless you really need to.
When finished, type exit in the terminal to drop privileges.
You can learn more about permissions in Linux filesystems here and from the permissions tag wiki.
Best Answer
That's not an error - it's telling you that you do not have permission to read the files in that directory as a normal user as you will see if you click on it.
If you want to see the contents of the directory you must do so as root. In a terminal type:
You notice that you have to enter your password. Now you have root privilege so you can view, edit and delete anything you want, so you should be careful because you could break your system - you shouldn't use root permission unless you really need to.
When finished, type
exit
in the terminal to drop privileges.You can learn more about permissions in Linux filesystems here and from the permissions tag wiki.