If you have issues uploading files, installing extensions or similar permission issues, check these items:
- Under Site -> Global Configuration -> Server you may have the wrong temp directory. Make sure the directory is valid (/tmp for example) and that Apache can write to it.
- Make sure Apache can write to the joomla installation. A simple soution is to change the ownership of the files:
- In ubuntu, run: chown -R www-data /var/www/vhosts/example.com/httpdocs
- In centos, run: chown -R httpd /var/www/vhosts/example.com/httpdocs