Unpacking the package… Could not create directory. Wordpress, Apache2, Ubuntu

The update creates a directory in wp-content/update inside the site directory. Linux does not set permissions automatically of child directories to those of the parent. Therefore wp-content/upload will not necessarily have 777 permissions.

Try change permissions of wp-content/update to 777. If this works it means that the owner of the WordPress folders is not the the user trying to update the site.

What worked for me was to add my ftp client to the group that the owner of the WordPress process. (How do I know which linux user Wordpress uses for plugin installation) to find the owner. and then set all directories to 775 permissions and files to 665 in the site directory.

chmod 775 $(find -type d)chmod 665 $(find -type f)

You need to give write permissions to the relevant directories. Ideally, you should do it only for the relevant file or folder and then revert the permissions back so as to not leave your site vulnerable.

You can fix this using the following commands from the command line (assuming that you are in the WordPress root folder):

# cd wp-content# chmod -R a+w plugins# chmod -R a+w themes# chmod -R a+w upgrade

The safest solution is to add Apache to the same group as the owner of the WordPress installation and change all group permissions to writeable.

A more detailed solution can be found at: http://techzog.com/wordpress/fixing-unpacking-package-could-not-create-directory-error-wordpress/